Merge branch 'akpm-current/current'

117 files changed, 5395 insertions, 1384 deletions

diff --git a/.gitattributes b/.gitattributes
index 89c411b5ce6b..4b32eaa9571e 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,2 +1,4 @@
 *.c   diff=cpp
 *.h   diff=cpp
+*.dtsi diff=dts
+*.dts  diff=dts
diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst
index 6e0da29e55f1..614179dc79a9 100644
--- a/Documentation/admin-guide/sysctl/kernel.rst
+++ b/Documentation/admin-guide/sysctl/kernel.rst
@@ -45,6 +45,7 @@ show up in /proc/sys/kernel:
 - hung_task_timeout_secs
 - hung_task_check_interval_secs
 - hung_task_warnings
+- hung_task_interval_warnings
 - hyperv_record_panic_msg
 - kexec_load_disabled
 - kptr_restrict
@@ -383,14 +384,29 @@ Possible values to set are in range {0..LONG_MAX/HZ}.
 hung_task_warnings:
 ===================
 
-The maximum number of warnings to report. During a check interval
-if a hung task is detected, this value is decreased by 1.
+The maximum number of warnings to report. If after timeout a hung
+task is present, this value is decreased by 1 every check interval,
+producing a warning.
 When this value reaches 0, no more warnings will be reported.
 This file shows up if CONFIG_DETECT_HUNG_TASK is enabled.
 
 -1: report an infinite number of warnings.
 
 
+hung_task_interval_warnings:
+===================
+
+The same as hung_task_warnings, but set the number of interval
+warnings to be issued about detected hung tasks during check
+interval. That will produce warnings *before* the timeout happens.
+If a hung task is detected during check interval, this value is
+decreased by 1. When this value reaches 0, only timeout warnings
+will be reported.
+This file shows up if CONFIG_DETECT_HUNG_TASK is enabled.
+
+-1: report an infinite number of check interval warnings.
+
+
 hyperv_record_panic_msg:
 ========================
 
diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt
index 1adbb8a371c7..fe43f4b30907 100644
--- a/Documentation/memory-barriers.txt
+++ b/Documentation/memory-barriers.txt
@@ -1873,12 +1873,16 @@ There are some more advanced barrier functions:
  (*) smp_mb__before_atomic();
  (*) smp_mb__after_atomic();
 
-     These are for use with atomic (such as add, subtract, increment and
-     decrement) functions that don't return a value, especially when used for
-     reference counting.  These functions do not imply memory barriers.
-
-     These are also used for atomic bitop functions that do not return a
-     value (such as set_bit and clear_bit).
+     These are for use with atomic RMW functions that do not imply memory
+     barriers, but where the code needs a memory barrier. Examples for atomic
+     RMW functions that do not imply are memory barrier are e.g. add,
+     subtract, (failed) conditional operations, _relaxed functions,
+     but not atomic_read or atomic_set. A common example where a memory
+     barrier may be required is when atomic ops are used for reference
+     counting.
+
+     These are also used for atomic RMW bitop functions that do not imply a
+     memory barrier (such as set_bit and clear_bit).
 
      As an example, consider a piece of code that marks an object as being dead
      and then decrements the object's reference count:
diff --git a/Documentation/process/deprecated.rst b/Documentation/process/deprecated.rst
index 179f2a5625a0..a0ffdc8daef3 100644
--- a/Documentation/process/deprecated.rst
+++ b/Documentation/process/deprecated.rst
@@ -84,7 +84,7 @@ buffer. This could result in linear overflows beyond the
 end of the buffer, leading to all kinds of misbehaviors. While
 `CONFIG_FORTIFY_SOURCE=y` and various compiler flags help reduce the
 risk of using this function, there is no good reason to add new uses of
-this function. The safe replacement is :c:func:`strscpy`.
+this function. The safe replacement is stracpy() or strscpy().
 
 strncpy() on NUL-terminated strings
 -----------------------------------
@@ -93,9 +93,9 @@ will be NUL terminated. This can lead to various linear read overflows
 and other misbehavior due to the missing termination. It also NUL-pads the
 destination buffer if the source contents are shorter than the destination
 buffer size, which may be a needless performance penalty for callers using
-only NUL-terminated strings. The safe replacement is :c:func:`strscpy`.
-(Users of :c:func:`strscpy` still needing NUL-padding will need an
-explicit :c:func:`memset` added.)
+only NUL-terminated strings. In this case, the safe replacement is
+stracpy() or strscpy(). If, however, the destination buffer still needs
+NUL-padding, the safe replacement is stracpy_pad().
 
 If a caller is using non-NUL-terminated strings, :c:func:`strncpy()` can
 still be used, but destinations should be marked with the `__nonstring
@@ -107,7 +107,7 @@ strlcpy()
 :c:func:`strlcpy` reads the entire source buffer first, possibly exceeding
 the given limit of bytes to copy. This is inefficient and can lead to
 linear read overflows if a source string is not NUL-terminated. The
-safe replacement is :c:func:`strscpy`.
+safe replacement is stracpy() or strscpy().
 
 Variable Length Arrays (VLAs)
 -----------------------------
diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h
index ea14a8bfc691..9019ed9f9c94 100644
--- a/arch/arc/include/asm/pgtable.h
+++ b/arch/arc/include/asm/pgtable.h
@@ -33,7 +33,6 @@
 #define _ASM_ARC_PGTABLE_H
 
 #include <linux/bits.h>
-#define __ARCH_USE_5LEVEL_HACK
 #include <asm-generic/pgtable-nopmd.h>
 #include <asm/page.h>
 #include <asm/mmu.h>	/* to propagate CONFIG_ARC_MMU_VER <n> */
diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c
index 3861543b66a0..fb86bc3e9b35 100644
--- a/arch/arc/mm/fault.c
+++ b/arch/arc/mm/fault.c
@@ -30,6 +30,7 @@ noinline static int handle_kernel_vaddr_fault(unsigned long address)
 	 * with the 'reference' page table.
 	 */
 	pgd_t *pgd, *pgd_k;
+	p4d_t *p4d, *p4d_k;
 	pud_t *pud, *pud_k;
 	pmd_t *pmd, *pmd_k;
 
@@ -39,8 +40,13 @@ noinline static int handle_kernel_vaddr_fault(unsigned long address)
 	if (!pgd_present(*pgd_k))
 		goto bad_area;
 
-	pud = pud_offset(pgd, address);
-	pud_k = pud_offset(pgd_k, address);
+	p4d = p4d_offset(pgd, address);
+	p4d_k = p4d_offset(pgd_k, address);
+	if (!p4d_present(*p4d_k))
+		goto bad_area;
+
+	pud = pud_offset(p4d, address);
+	pud_k = pud_offset(p4d_k, address);
 	if (!pud_present(*pud_k))
 		goto bad_area;
 
diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
index a4856bfaedf3..fc8849e4f72e 100644
--- a/arch/arc/mm/highmem.c
+++ b/arch/arc/mm/highmem.c
@@ -111,12 +111,14 @@ EXPORT_SYMBOL(__kunmap_atomic);
 static noinline pte_t * __init alloc_kmap_pgtable(unsigned long kvaddr)
 {
 	pgd_t *pgd_k;
+	p4d_t *p4d_k;
 	pud_t *pud_k;
 	pmd_t *pmd_k;
 	pte_t *pte_k;
 
 	pgd_k = pgd_offset_k(kvaddr);
-	pud_k = pud_offset(pgd_k, kvaddr);
+	p4d_k = p4d_offset(pgd_k, kvaddr);
+	pud_k = pud_offset(p4d_k, kvaddr);
 	pmd_k = pmd_offset(pud_k, kvaddr);
 
 	pte_k = (pte_t *)memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 60c929f3683b..d10247fab0fd 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1069,7 +1069,6 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct zone *zone;
 
 	/*
 	 * FIXME: Cleanup page tables (also in arch_add_memory() in case
@@ -1078,7 +1077,6 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 	 * unplug. ARCH_ENABLE_MEMORY_HOTREMOVE must not be
 	 * unlocked yet.
 	 */
-	zone = page_zone(pfn_to_page(start_pfn));
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 }
 #endif
diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
index bf9df2625bc8..a6dd80a2c939 100644
--- a/arch/ia64/mm/init.c
+++ b/arch/ia64/mm/init.c
@@ -689,9 +689,7 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct zone *zone;
 
-	zone = page_zone(pfn_to_page(start_pfn));
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 }
 #endif
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index be941d382c8d..97e5922cb52e 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -130,10 +130,9 @@ void __ref arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct page *page = pfn_to_page(start_pfn) + vmem_altmap_offset(altmap);
 	int ret;
 
-	__remove_pages(page_zone(page), start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 
 	/* Remove htab bolted mappings for this section of memory */
 	start = (unsigned long)__va(start);
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index a124f19f7b3c..c1d96e588152 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -291,10 +291,8 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct zone *zone;
 
-	zone = page_zone(pfn_to_page(start_pfn));
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 	vmem_remove_mapping(start, size);
 }
 #endif /* CONFIG_MEMORY_HOTPLUG */
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index dfdbaa50946e..d1b1ff2be17a 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -434,9 +434,7 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = PFN_DOWN(start);
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct zone *zone;
 
-	zone = page_zone(pfn_to_page(start_pfn));
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 }
 #endif /* CONFIG_MEMORY_HOTPLUG */
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 930edeb41ec3..0a74407ef92e 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -865,10 +865,8 @@ void arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct zone *zone;
 
-	zone = page_zone(pfn_to_page(start_pfn));
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 }
 #endif
 
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index a6b5c653727b..b8541d77452c 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -1212,10 +1212,8 @@ void __ref arch_remove_memory(int nid, u64 start, u64 size,
 {
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 	unsigned long nr_pages = size >> PAGE_SHIFT;
-	struct page *page = pfn_to_page(start_pfn) + vmem_altmap_offset(altmap);
-	struct zone *zone = page_zone(page);
 
-	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	__remove_pages(start_pfn, nr_pages, altmap);
 	kernel_physical_mapping_remove(start, start + size);
 }
 #endif /* CONFIG_MEMORY_HOTPLUG */
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 55907c27075b..a757d9ed88a7 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -538,12 +538,7 @@ static ssize_t soft_offline_page_store(struct device *dev,
 	if (kstrtoull(buf, 0, &pfn) < 0)
 		return -EINVAL;
 	pfn >>= PAGE_SHIFT;
-	if (!pfn_valid(pfn))
-		return -ENXIO;
-	/* Only online pages can be soft-offlined (esp., not ZONE_DEVICE). */
-	if (!pfn_to_online_page(pfn))
-		return -EIO;
-	ret = soft_offline_page(pfn_to_page(pfn), 0);
+	ret = soft_offline_page(pfn, 0);
 	return ret == 0 ? count : ret;
 }
 
diff --git a/drivers/base/node.c b/drivers/base/node.c
index 296546ffed6c..98a31bafc8a2 100644
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -496,20 +496,17 @@ static ssize_t node_read_vmstat(struct device *dev,
 	int n = 0;
 
 	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
-		n += sprintf(buf+n, "%s %lu\n", vmstat_text[i],
+		n += sprintf(buf+n, "%s %lu\n", zone_stat_name(i),
 			     sum_zone_node_page_state(nid, i));
 
 #ifdef CONFIG_NUMA
 	for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
-		n += sprintf(buf+n, "%s %lu\n",
-			     vmstat_text[i + NR_VM_ZONE_STAT_ITEMS],
+		n += sprintf(buf+n, "%s %lu\n", numa_stat_name(i),
 			     sum_zone_numa_state(nid, i));
 #endif
 
 	for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
-		n += sprintf(buf+n, "%s %lu\n",
-			     vmstat_text[i + NR_VM_ZONE_STAT_ITEMS +
-			     NR_VM_NUMA_STAT_ITEMS],
+		n += sprintf(buf+n, "%s %lu\n", node_stat_name(i),
 			     node_page_state(pgdat, i));
 
 	return n;
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index 34bd73526afd..da6ced15c6c5 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -680,9 +680,7 @@ static void hv_page_online_one(struct hv_hotadd_state *has, struct page *pg)
 		__ClearPageOffline(pg);
 
 	/* This frame is currently backed; online the page. */
-	__online_page_set_limits(pg);
-	__online_page_increment_counters(pg);
-	__online_page_free(pg);
+	generic_online_page(pg, 0);
 
 	lockdep_assert_held(&dm_device.ha_lock);
 	dm_device.num_pages_onlined++;
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 5bae515c8e25..4f2e78a5e4db 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -374,7 +374,6 @@ static void xen_online_page(struct page *page, unsigned int order)
 	mutex_lock(&balloon_mutex);
 	for (i = 0; i < size; i++) {
 		p = pfn_to_page(start_pfn + i);
-		__online_page_set_limits(p);
 		balloon_append(p);
 	}
 	mutex_unlock(&balloon_mutex);
diff --git a/fs/aio.c b/fs/aio.c
index 0d9a559d488c..1218a453d6db 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1287,12 +1287,9 @@ static long read_events(struct kioctx *ctx, long min_nr, long nr,
 	 * the ringbuffer empty. So in practice we should be ok, but it's
 	 * something to be aware of when touching this code.
 	 */
-	if (until == 0)
-		aio_read_events(ctx, min_nr, nr, event, &ret);
-	else
-		wait_event_interruptible_hrtimeout(ctx->wait,
-				aio_read_events(ctx, min_nr, nr, event, &ret),
-				until);
+	wait_event_interruptible_hrtimeout(ctx->wait,
+			aio_read_events(ctx, min_nr, nr, event, &ret),
+			until);
 	return ret;
 }
 
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index c5642bcb6b46..54f21926940e 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -404,6 +404,17 @@ static unsigned long total_mapping_size(const struct elf_phdr *cmds, int nr)
 				ELF_PAGESTART(cmds[first_idx].p_vaddr);
 }
 
+static int elf_read(struct file *file, void *buf, size_t len, loff_t pos)
+{
+	ssize_t rv;
+
+	rv = kernel_read(file, buf, len, &pos);
+	if (unlikely(rv != len)) {
+		return (rv < 0) ? rv : -EIO;
+	}
+	return 0;
+}
+
 /**
  * load_elf_phdrs() - load ELF program headers
  * @elf_ex:   ELF header of the binary whose program headers should be loaded
@@ -418,7 +429,6 @@ static struct elf_phdr *load_elf_phdrs(const struct elfhdr *elf_ex,
 {
 	struct elf_phdr *elf_phdata = NULL;
 	int retval, err = -1;
-	loff_t pos = elf_ex->e_phoff;
 	unsigned int size;
 
 	/*
@@ -439,9 +449,9 @@ static struct elf_phdr *load_elf_phdrs(const struct elfhdr *elf_ex,
 		goto out;
 
 	/* Read in the program headers */
-	retval = kernel_read(elf_file, elf_phdata, size, &pos);
-	if (retval != size) {
-		err = (retval < 0) ? retval : -EIO;
+	retval = elf_read(elf_file, elf_phdata, size, elf_ex->e_phoff);
+	if (retval < 0) {
+		err = retval;
 		goto out;
 	}
 
@@ -544,7 +554,7 @@ static inline int make_prot(u32 p_flags)
    an ELF header */
 
 static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
-		struct file *interpreter, unsigned long *interp_map_addr,
+		struct file *interpreter,
 		unsigned long no_base, struct elf_phdr *interp_elf_phdata)
 {
 	struct elf_phdr *eppnt;
@@ -590,8 +600,6 @@ static unsigned long load_elf_interp(struct elfhdr *interp_elf_ex,
 			map_addr = elf_map(interpreter, load_addr + vaddr,
 					eppnt, elf_prot, elf_type, total_size);
 			total_size = 0;
-			if (!*interp_map_addr)
-				*interp_map_addr = map_addr;
 			error = map_addr;
 			if (BAD_ADDR(map_addr))
 				goto out;
@@ -722,7 +730,6 @@ static int load_elf_binary(struct linux_binprm *bprm)
 	elf_ppnt = elf_phdata;
 	for (i = 0; i < loc->elf_ex.e_phnum; i++, elf_ppnt++) {
 		char *elf_interpreter;
-		loff_t pos;
 
 		if (elf_ppnt->p_type != PT_INTERP)
 			continue;
@@ -740,14 +747,10 @@ static int load_elf_binary(struct linux_binprm *bprm)
 		if (!elf_interpreter)
 			goto out_free_ph;
 
-		pos = elf_ppnt->p_offset;
-		retval = kernel_read(bprm->file, elf_interpreter,
-				     elf_ppnt->p_filesz, &pos);
-		if (retval != elf_ppnt->p_filesz) {
-			if (retval >= 0)
-				retval = -EIO;
+		retval = elf_read(bprm->file, elf_interpreter, elf_ppnt->p_filesz,
+				  elf_ppnt->p_offset);
+		if (retval < 0)
 			goto out_free_interp;
-		}
 		/* make sure path is NULL terminated */
 		retval = -ENOEXEC;
 		if (elf_interpreter[elf_ppnt->p_filesz - 1] != '\0')
@@ -766,14 +769,10 @@ static int load_elf_binary(struct linux_binprm *bprm)
 		would_dump(bprm, interpreter);
 
 		/* Get the exec headers */
-		pos = 0;
-		retval = kernel_read(interpreter, &loc->interp_elf_ex,
-				     sizeof(loc->interp_elf_ex), &pos);
-		if (retval != sizeof(loc->interp_elf_ex)) {
-			if (retval >= 0)
-				retval = -EIO;
+		retval = elf_read(interpreter, &loc->interp_elf_ex,
+				  sizeof(loc->interp_elf_ex), 0);
+		if (retval < 0)
 			goto out_free_dentry;
-		}
 
 		break;
 
@@ -1054,11 +1053,8 @@ out_free_interp:
 	}
 
 	if (interpreter) {
-		unsigned long interp_map_addr = 0;
-
 		elf_entry = load_elf_interp(&loc->interp_elf_ex,
 					    interpreter,
-					    &interp_map_addr,
 					    load_bias, interp_elf_phdata);
 		if (!IS_ERR((void *)elf_entry)) {
 			/*
@@ -1179,11 +1175,10 @@ static int load_elf_library(struct file *file)
 	unsigned long elf_bss, bss, len;
 	int retval, error, i, j;
 	struct elfhdr elf_ex;
-	loff_t pos = 0;
 
 	error = -ENOEXEC;
-	retval = kernel_read(file, &elf_ex, sizeof(elf_ex), &pos);
-	if (retval != sizeof(elf_ex))
+	retval = elf_read(file, &elf_ex, sizeof(elf_ex), 0);
+	if (retval < 0)
 		goto out;
 
 	if (memcmp(elf_ex.e_ident, ELFMAG, SELFMAG) != 0)
@@ -1208,9 +1203,8 @@ static int load_elf_library(struct file *file)
 
 	eppnt = elf_phdata;
 	error = -ENOEXEC;
-	pos =  elf_ex.e_phoff;
-	retval = kernel_read(file, eppnt, j, &pos);
-	if (retval != j)
+	retval = elf_read(file, eppnt, j, elf_ex.e_phoff);
+	if (retval < 0)
 		goto out_free_ph;
 
 	for (j = 0, i = 0; i<elf_ex.e_phnum; i++)
diff --git a/fs/buffer.c b/fs/buffer.c
index 86a38b979323..131d39ec7d31 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -956,10 +956,20 @@ grow_dev_page(struct block_device *bdev, sector_t block,
 			end_block = init_page_buffers(page, bdev,
 						(sector_t)index << sizebits,
 						size);
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+			current->getblk_executed |= 0x01;
+#endif
 			goto done;
 		}
-		if (!try_to_free_buffers(page))
+		if (!try_to_free_buffers(page)) {
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+			current->getblk_executed |= 0x02;
+#endif
 			goto failed;
+		}
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+		current->getblk_executed |= 0x04;
+#endif
 	}
 
 	/*
@@ -979,6 +989,9 @@ grow_dev_page(struct block_device *bdev, sector_t block,
 	spin_unlock(&inode->i_mapping->private_lock);
 done:
 	ret = (block < end_block) ? 1 : -ENXIO;
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+	current->getblk_executed |= 0x08;
+#endif
 failed:
 	unlock_page(page);
 	put_page(page);
@@ -1034,6 +1047,12 @@ __getblk_slow(struct block_device *bdev, sector_t block,
 		return NULL;
 	}
 
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+	current->getblk_stamp = jiffies;
+	current->getblk_executed = 0;
+	current->getblk_bh_count = 0;
+	current->getblk_bh_state = 0;
+#endif
 	for (;;) {
 		struct buffer_head *bh;
 		int ret;
@@ -1045,6 +1064,24 @@ __getblk_slow(struct block_device *bdev, sector_t block,
 		ret = grow_buffers(bdev, block, size, gfp);
 		if (ret < 0)
 			return NULL;
+
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+		if (!time_after(jiffies, current->getblk_stamp + 3 * HZ))
+			continue;
+		printk(KERN_ERR "%s(%u): getblk(): executed=%x bh_count=%d bh_state=%lx bdev_super_blocksize=%ld size=%u bdev_super_blocksize_bits=%d bdev_inode_blkbits=%d\n",
+		       current->comm, current->pid, current->getblk_executed,
+		       current->getblk_bh_count, current->getblk_bh_state,
+		       IS_ERR_OR_NULL(bdev->bd_super) ? -1L :
+		       bdev->bd_super->s_blocksize, size,
+		       IS_ERR_OR_NULL(bdev->bd_super) ? -1 :
+		       bdev->bd_super->s_blocksize_bits,
+		       IS_ERR_OR_NULL(bdev->bd_inode) ? -1 :
+		       bdev->bd_inode->i_blkbits);
+		current->getblk_executed = 0;
+		current->getblk_bh_count = 0;
+		current->getblk_bh_state = 0;
+		current->getblk_stamp = jiffies;
+#endif
 	}
 }
 
@@ -3223,6 +3260,11 @@ EXPORT_SYMBOL(sync_dirty_buffer);
  */
 static inline int buffer_busy(struct buffer_head *bh)
 {
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+	current->getblk_executed |= 0x80;
+	current->getblk_bh_count = atomic_read(&bh->b_count);
+	current->getblk_bh_state = bh->b_state;
+#endif
 	return atomic_read(&bh->b_count) |
 		(bh->b_state & ((1 << BH_Dirty) | (1 << BH_Lock)));
 }
@@ -3261,11 +3303,18 @@ int try_to_free_buffers(struct page *page)
 	int ret = 0;
 
 	BUG_ON(!PageLocked(page));
-	if (PageWriteback(page))
+	if (PageWriteback(page)) {
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+		current->getblk_executed |= 0x10;
+#endif
 		return 0;
+	}
 
 	if (mapping == NULL) {		/* can this still happen? */
 		ret = drop_buffers(page, &buffers_to_free);
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+		current->getblk_executed |= 0x20;
+#endif
 		goto out;
 	}
 
@@ -3289,6 +3338,9 @@ int try_to_free_buffers(struct page *page)
 	if (ret)
 		cancel_dirty_page(page);
 	spin_unlock(&mapping->private_lock);
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+	current->getblk_executed |= 0x40;
+#endif
 out:
 	if (buffers_to_free) {
 		struct buffer_head *bh = buffers_to_free;
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index c4159bcc05d9..67a395039268 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -551,28 +551,23 @@ out_unlock:
  */
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 
-static struct nested_calls poll_safewake_ncalls;
-
-static int ep_poll_wakeup_proc(void *priv, void *cookie, int call_nests)
-{
-	unsigned long flags;
-	wait_queue_head_t *wqueue = (wait_queue_head_t *)cookie;
-
-	spin_lock_irqsave_nested(&wqueue->lock, flags, call_nests + 1);
-	wake_up_locked_poll(wqueue, EPOLLIN);
-	spin_unlock_irqrestore(&wqueue->lock, flags);
-
-	return 0;
-}
+static DEFINE_PER_CPU(int, wakeup_nest);
 
 static void ep_poll_safewake(wait_queue_head_t *wq)
 {
-	int this_cpu = get_cpu();
-
-	ep_call_nested(&poll_safewake_ncalls,
-		       ep_poll_wakeup_proc, NULL, wq, (void *) (long) this_cpu);
+	unsigned long flags;
+	int subclass;
 
-	put_cpu();
+	local_irq_save(flags);
+	preempt_disable();
+	subclass = __this_cpu_read(wakeup_nest);
+	spin_lock_nested(&wq->lock, subclass + 1);
+	__this_cpu_inc(wakeup_nest);
+	wake_up_locked_poll(wq, POLLIN);
+	__this_cpu_dec(wakeup_nest);
+	spin_unlock(&wq->lock);
+	local_irq_restore(flags);
+	preempt_enable();
 }
 
 #else
@@ -671,7 +666,6 @@ static __poll_t ep_scan_ready_list(struct eventpoll *ep,
 			      void *priv, int depth, bool ep_locked)
 {
 	__poll_t res;
-	int pwake = 0;
 	struct epitem *epi, *nepi;
 	LIST_HEAD(txlist);
 
@@ -738,26 +732,11 @@ static __poll_t ep_scan_ready_list(struct eventpoll *ep,
 	 */
 	list_splice(&txlist, &ep->rdllist);
 	__pm_relax(ep->ws);
-
-	if (!list_empty(&ep->rdllist)) {
-		/*
-		 * Wake up (if active) both the eventpoll wait list and
-		 * the ->poll() wait list (delayed after we release the lock).
-		 */
-		if (waitqueue_active(&ep->wq))
-			wake_up(&ep->wq);
-		if (waitqueue_active(&ep->poll_wait))
-			pwake++;
-	}
 	write_unlock_irq(&ep->lock);
 
 	if (!ep_locked)
 		mutex_unlock(&ep->mtx);
 
-	/* We have to call this outside the lock */
-	if (pwake)
-		ep_poll_safewake(&ep->poll_wait);
-
 	return res;
 }
 
@@ -2370,11 +2349,6 @@ static int __init eventpoll_init(void)
 	 */
 	ep_nested_calls_init(&poll_loop_ncalls);
 
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-	/* Initialize the structure used to perform safe poll wait head wake ups */
-	ep_nested_calls_init(&poll_safewake_ncalls);
-#endif
-
 	/*
 	 * We can have many thousands of epitems, so prevent this from
 	 * using an extra cache line on 64-bit (and smaller) CPUs
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index a478df035651..b9561bbf1dd9 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -440,7 +440,7 @@ static void remove_inode_hugepages(struct inode *inode, loff_t lstart,
 			u32 hash;
 
 			index = page->index;
-			hash = hugetlb_fault_mutex_hash(h, mapping, index, 0);
+			hash = hugetlb_fault_mutex_hash(mapping, index);
 			mutex_lock(&hugetlb_fault_mutex_table[hash]);
 
 			/*
@@ -644,7 +644,7 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset,
 		addr = index * hpage_size;
 
 		/* mutex taken here, fault path and hole punch */
-		hash = hugetlb_fault_mutex_hash(h, mapping, index, addr);
+		hash = hugetlb_fault_mutex_hash(mapping, index);
 		mutex_lock(&hugetlb_fault_mutex_table[hash]);
 
 		/* See if already present in mapping to avoid alloc/free */
diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c
index 3e7da392aa6f..bb981ec76456 100644
--- a/fs/ocfs2/acl.c
+++ b/fs/ocfs2/acl.c
@@ -327,8 +327,8 @@ int ocfs2_acl_chmod(struct inode *inode, struct buffer_head *bh)
 	down_read(&OCFS2_I(inode)->ip_xattr_sem);
 	acl = ocfs2_get_acl_nolock(inode, ACL_TYPE_ACCESS, bh);
 	up_read(&OCFS2_I(inode)->ip_xattr_sem);
-	if (IS_ERR(acl) || !acl)
-		return PTR_ERR(acl);
+	if (IS_ERR_OR_NULL(acl))
+		return PTR_ERR_OR_ZERO(acl);
 	ret = __posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
 	if (ret)
 		return ret;
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 53939bf9d7d2..9876db52913a 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2098,53 +2098,89 @@ static int ocfs2_is_io_unaligned(struct inode *inode, size_t count, loff_t pos)
 	return 0;
 }
 
-static int ocfs2_prepare_inode_for_refcount(struct inode *inode,
-					    struct file *file,
-					    loff_t pos, size_t count,
-					    int *meta_level)
+static int ocfs2_inode_lock_for_extent_tree(struct inode *inode,
+					    struct buffer_head **di_bh,
+					    int meta_level,
+					    int overwrite_io,
+					    int write_sem,
+					    int wait)
 {
-	int ret;
-	struct buffer_head *di_bh = NULL;
-	u32 cpos = pos >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
-	u32 clusters =
-		ocfs2_clusters_for_bytes(inode->i_sb, pos + count) - cpos;
+	int ret = 0;
 
-	ret = ocfs2_inode_lock(inode, &di_bh, 1);
-	if (ret) {
-		mlog_errno(ret);
+	if (wait)
+		ret = ocfs2_inode_lock(inode, NULL, meta_level);
+	else
+		ret = ocfs2_try_inode_lock(inode,
+			overwrite_io ? NULL : di_bh, meta_level);
+	if (ret < 0)
 		goto out;
+
+	if (wait) {
+		if (write_sem)
+			down_write(&OCFS2_I(inode)->ip_alloc_sem);
+		else
+			down_read(&OCFS2_I(inode)->ip_alloc_sem);
+	} else {
+		if (write_sem)
+			ret = down_write_trylock(&OCFS2_I(inode)->ip_alloc_sem);
+		else
+			ret = down_read_trylock(&OCFS2_I(inode)->ip_alloc_sem);
+
+		if (!ret) {
+			ret = -EAGAIN;
+			goto out_unlock;
+		}
 	}
 
-	*meta_level = 1;
+	return ret;
 
-	ret = ocfs2_refcount_cow(inode, di_bh, cpos, clusters, UINT_MAX);
-	if (ret)
-		mlog_errno(ret);
+out_unlock:
+	brelse(*di_bh);
+	ocfs2_inode_unlock(inode, meta_level);
 out:
-	brelse(di_bh);
 	return ret;
 }
 
+static void ocfs2_inode_unlock_for_extent_tree(struct inode *inode,
+					       struct buffer_head **di_bh,
+					       int meta_level,
+					       int write_sem)
+{
+	if (write_sem)
+		up_write(&OCFS2_I(inode)->ip_alloc_sem);
+	else
+		up_read(&OCFS2_I(inode)->ip_alloc_sem);
+
+	brelse(*di_bh);
+	*di_bh = NULL;
+
+	if (meta_level >= 0)
+		ocfs2_inode_unlock(inode, meta_level);
+}
+
 static int ocfs2_prepare_inode_for_write(struct file *file,
 					 loff_t pos, size_t count, int wait)
 {
 	int ret = 0, meta_level = 0, overwrite_io = 0;
+	int write_sem = 0;
 	struct dentry *dentry = file->f_path.dentry;
 	struct inode *inode = d_inode(dentry);
 	struct buffer_head *di_bh = NULL;
+	u32 cpos;
+	u32 clusters;
 
 	/*
 	 * We start with a read level meta lock and only jump to an ex
 	 * if we need to make modifications here.
 	 */
 	for(;;) {
-		if (wait)
-			ret = ocfs2_inode_lock(inode, NULL, meta_level);
-		else
-			ret = ocfs2_try_inode_lock(inode,
-				overwrite_io ? NULL : &di_bh, meta_level);
+		ret = ocfs2_inode_lock_for_extent_tree(inode,
+						       &di_bh,
+						       meta_level,
+						       overwrite_io,
+						       write_sem,
+						       wait);
 		if (ret < 0) {
-			meta_level = -1;
 			if (ret != -EAGAIN)
 				mlog_errno(ret);
 			goto out;
@@ -2156,15 +2192,8 @@ static int ocfs2_prepare_inode_for_write(struct file *file,
 		 */
 		if (!wait && !overwrite_io) {
 			overwrite_io = 1;
-			if (!down_read_trylock(&OCFS2_I(inode)->ip_alloc_sem)) {
-				ret = -EAGAIN;
-				goto out_unlock;
-			}
 
 			ret = ocfs2_overwrite_io(inode, di_bh, pos, count);
-			brelse(di_bh);
-			di_bh = NULL;
-			up_read(&OCFS2_I(inode)->ip_alloc_sem);
 			if (ret < 0) {
 				if (ret != -EAGAIN)
 					mlog_errno(ret);
@@ -2183,7 +2212,10 @@ static int ocfs2_prepare_inode_for_write(struct file *file,
 		 * set inode->i_size at the end of a write. */
 		if (should_remove_suid(dentry)) {
 			if (meta_level == 0) {
-				ocfs2_inode_unlock(inode, meta_level);
+				ocfs2_inode_unlock_for_extent_tree(inode,
+								   &di_bh,
+								   meta_level,
+								   write_sem);
 				meta_level = 1;
 				continue;
 			}
@@ -2197,18 +2229,32 @@ static int ocfs2_prepare_inode_for_write(struct file *file,
 
 		ret = ocfs2_check_range_for_refcount(inode, pos, count);
 		if (ret == 1) {
-			ocfs2_inode_unlock(inode, meta_level);
-			meta_level = -1;
-
-			ret = ocfs2_prepare_inode_for_refcount(inode,
-							       file,
-							       pos,
-							       count,
-							       &meta_level);
+			ocfs2_inode_unlock_for_extent_tree(inode,
+							   &di_bh,
+							   meta_level,
+							   write_sem);
+			ret = ocfs2_inode_lock_for_extent_tree(inode,
+							       &di_bh,
+							       meta_level,
+							       overwrite_io,
+							       1,
+							       wait);
+			write_sem = 1;
+			if (ret < 0) {
+				if (ret != -EAGAIN)
+					mlog_errno(ret);
+				goto out;
+			}
+
+			cpos = pos >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
+			clusters =
+				ocfs2_clusters_for_bytes(inode->i_sb, pos + count) - cpos;
+			ret = ocfs2_refcount_cow(inode, di_bh, cpos, clusters, UINT_MAX);
 		}
 
 		if (ret < 0) {
-			mlog_errno(ret);
+			if (ret != -EAGAIN)
+				mlog_errno(ret);
 			goto out_unlock;
 		}
 
@@ -2219,10 +2265,10 @@ out_unlock:
 	trace_ocfs2_prepare_inode_for_write(OCFS2_I(inode)->ip_blkno,
 					    pos, count, wait);
 
-	brelse(di_bh);
-
-	if (meta_level >= 0)
-		ocfs2_inode_unlock(inode, meta_level);
+	ocfs2_inode_unlock_for_extent_tree(inode,
+					   &di_bh,
+					   meta_level,
+					   write_sem);
 
 out:
 	return ret;
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 64e9ee1b129e..074e9585c699 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -138,8 +138,12 @@ static int proc_getattr(const struct path *path, struct kstat *stat,
 {
 	struct inode *inode = d_inode(path->dentry);
 	struct proc_dir_entry *de = PDE(inode);
-	if (de && de->nlink)
-		set_nlink(inode, de->nlink);
+	if (de) {
+		nlink_t nlink = READ_ONCE(de->nlink);
+		if (nlink > 0) {
+			set_nlink(inode, nlink);
+		}
+	}
 
 	generic_fillattr(inode, stat);
 	return 0;
@@ -159,7 +163,6 @@ static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret,
 {
 	const char     		*cp = name, *next;
 	struct proc_dir_entry	*de;
-	unsigned int		len;
 
 	de = *ret;
 	if (!de)
@@ -170,13 +173,12 @@ static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret,
 		if (!next)
 			break;
 
-		len = next - cp;
-		de = pde_subdir_find(de, cp, len);
+		de = pde_subdir_find(de, cp, next - cp);
 		if (!de) {
 			WARN(1, "name '%s'\n", name);
 			return -ENOENT;
 		}
-		cp += len + 1;
+		cp = next + 1;
 	}
 	*residual = cp;
 	*ret = de;
@@ -362,6 +364,7 @@ struct proc_dir_entry *proc_register(struct proc_dir_entry *dir,
 		write_unlock(&proc_subdir_lock);
 		goto out_free_inum;
 	}
+	dir->nlink++;
 	write_unlock(&proc_subdir_lock);
 
 	return dp;
@@ -472,10 +475,7 @@ struct proc_dir_entry *proc_mkdir_data(const char *name, umode_t mode,
 		ent->data = data;
 		ent->proc_fops = &proc_dir_operations;
 		ent->proc_iops = &proc_dir_inode_operations;
-		parent->nlink++;
 		ent = proc_register(parent, ent);
-		if (!ent)
-			parent->nlink--;
 	}
 	return ent;
 }
@@ -505,10 +505,7 @@ struct proc_dir_entry *proc_create_mount_point(const char *name)
 		ent->data = NULL;
 		ent->proc_fops = NULL;
 		ent->proc_iops = NULL;
-		parent->nlink++;
 		ent = proc_register(parent, ent);
-		if (!ent)
-			parent->nlink--;
 	}
 	return ent;
 }
@@ -666,8 +663,12 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
 	len = strlen(fn);
 
 	de = pde_subdir_find(parent, fn, len);
-	if (de)
+	if (de) {
 		rb_erase(&de->subdir_node, &parent->subdir);
+		if (S_ISDIR(de->mode)) {
+			parent->nlink--;
+		}
+	}
 	write_unlock(&proc_subdir_lock);
 	if (!de) {
 		WARN(1, "name '%s'\n", name);
@@ -676,9 +677,6 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
 
 	proc_entry_rundown(de);
 
-	if (S_ISDIR(de->mode))
-		parent->nlink--;
-	de->nlink = 0;
 	WARN(pde_subdir_first(de),
 	     "%s: removing non-empty directory '%s/%s', leaking at least '%s'\n",
 	     __func__, de->parent->name, de->name, pde_subdir_first(de)->name);
@@ -714,13 +712,12 @@ int remove_proc_subtree(const char *name, struct proc_dir_entry *parent)
 			de = next;
 			continue;
 		}
-		write_unlock(&proc_subdir_lock);
-
-		proc_entry_rundown(de);
 		next = de->parent;
 		if (S_ISDIR(de->mode))
 			next->nlink--;
-		de->nlink = 0;
+		write_unlock(&proc_subdir_lock);
+
+		proc_entry_rundown(de);
 		if (de == root)
 			break;
 		pde_put(de);
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index cd0c8d5ce9a1..0f3b557c9b77 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -197,8 +197,8 @@ extern ssize_t proc_simple_write(struct file *, const char __user *, size_t, lof
  * inode.c
  */
 struct pde_opener {
-	struct file *file;
 	struct list_head lh;
+	struct file *file;
 	bool closing;
 	struct completion *c;
 } __randomize_layout;
diff --git a/fs/proc/page.c b/fs/proc/page.c
index 7c952ee732e6..e40dbfe1168e 100644
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -97,7 +97,10 @@ u64 stable_page_flags(struct page *page)
 	 * it differentiates a memory hole from a page with no flags
 	 */
 	if (!page)
-		return 1 << KPF_NOPAGE;
+		return BIT_ULL(KPF_NOPAGE);
+
+	if (pfn_zone_device_reserved(page_to_pfn(page)))
+		return BIT_ULL(KPF_RESERVED);
 
 	k = page->flags;
 	u = 0;
@@ -109,22 +112,22 @@ u64 stable_page_flags(struct page *page)
 	 * simple test in page_mapped() is not enough.
 	 */
 	if (!PageSlab(page) && page_mapped(page))
-		u |= 1 << KPF_MMAP;
+		u |= BIT_ULL(KPF_MMAP);
 	if (PageAnon(page))
-		u |= 1 << KPF_ANON;
+		u |= BIT_ULL(KPF_ANON);
 	if (PageKsm(page))
-		u |= 1 << KPF_KSM;
+		u |= BIT_ULL(KPF_KSM);
 
 	/*
 	 * compound pages: export both head/tail info
 	 * they together define a compound page's start/end pos and order
 	 */
 	if (PageHead(page))
-		u |= 1 << KPF_COMPOUND_HEAD;
+		u |= BIT_ULL(KPF_COMPOUND_HEAD);
 	if (PageTail(page))
-		u |= 1 << KPF_COMPOUND_TAIL;
+		u |= BIT_ULL(KPF_COMPOUND_TAIL);
 	if (PageHuge(page))
-		u |= 1 << KPF_HUGE;
+		u |= BIT_ULL(KPF_HUGE);
 	/*
 	 * PageTransCompound can be true for non-huge compound pages (slab
 	 * pages or pages allocated by drivers with __GFP_COMP) because it
@@ -135,14 +138,13 @@ u64 stable_page_flags(struct page *page)
 		struct page *head = compound_head(page);
 
 		if (PageLRU(head) || PageAnon(head))
-			u |= 1 << KPF_THP;
+			u |= BIT_ULL(KPF_THP);
 		else if (is_huge_zero_page(head)) {
-			u |= 1 << KPF_ZERO_PAGE;
-			u |= 1 << KPF_THP;
+			u |= BIT_ULL(KPF_ZERO_PAGE);
+			u |= BIT_ULL(KPF_THP);
 		}
 	} else if (is_zero_pfn(page_to_pfn(page)))
-		u |= 1 << KPF_ZERO_PAGE;
-
+		u |= BIT_ULL(KPF_ZERO_PAGE);
 
 	/*
 	 * Caveats on high order pages: page->_refcount will only be set
@@ -150,23 +152,23 @@ u64 stable_page_flags(struct page *page)
 	 * SLOB won't set PG_slab at all on compound pages.
 	 */
 	if (PageBuddy(page))
-		u |= 1 << KPF_BUDDY;
+		u |= BIT_ULL(KPF_BUDDY);
 	else if (page_count(page) == 0 && is_free_buddy_page(page))
-		u |= 1 << KPF_BUDDY;
+		u |= BIT_ULL(KPF_BUDDY);
 
 	if (PageOffline(page))
-		u |= 1 << KPF_OFFLINE;
+		u |= BIT_ULL(KPF_OFFLINE);
 	if (PageTable(page))
-		u |= 1 << KPF_PGTABLE;
+		u |= BIT_ULL(KPF_PGTABLE);
 
 	if (page_is_idle(page))
-		u |= 1 << KPF_IDLE;
+		u |= BIT_ULL(KPF_IDLE);
 
 	u |= kpf_copy_bit(k, KPF_LOCKED,	PG_locked);
 
 	u |= kpf_copy_bit(k, KPF_SLAB,		PG_slab);
 	if (PageTail(page) && PageSlab(compound_head(page)))
-		u |= 1 << KPF_SLAB;
+		u |= BIT_ULL(KPF_SLAB);
 
 	u |= kpf_copy_bit(k, KPF_ERROR,		PG_error);
 	u |= kpf_copy_bit(k, KPF_DIRTY,		PG_dirty);
@@ -179,7 +181,7 @@ u64 stable_page_flags(struct page *page)
 	u |= kpf_copy_bit(k, KPF_RECLAIM,	PG_reclaim);
 
 	if (PageSwapCache(page))
-		u |= 1 << KPF_SWAPCACHE;
+		u |= BIT_ULL(KPF_SWAPCACHE);
 	u |= kpf_copy_bit(k, KPF_SWAPBACKED,	PG_swapbacked);
 
 	u |= kpf_copy_bit(k, KPF_UNEVICTABLE,	PG_unevictable);
diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c
index d82636e8eb65..35624ca2a2f9 100644
--- a/fs/ramfs/inode.c
+++ b/fs/ramfs/inode.c
@@ -147,6 +147,17 @@ static int ramfs_symlink(struct inode * dir, struct dentry *dentry, const char *
 	return error;
 }
 
+static int ramfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+	struct inode *inode;
+
+	inode = ramfs_get_inode(dir->i_sb, dir, mode, 0);
+	if (!inode)
+		return -ENOSPC;
+	d_tmpfile(dentry, inode);
+	return 0;
+}
+
 static const struct inode_operations ramfs_dir_inode_operations = {
 	.create		= ramfs_create,
 	.lookup		= simple_lookup,
@@ -157,6 +168,7 @@ static const struct inode_operations ramfs_dir_inode_operations = {
 	.rmdir		= simple_rmdir,
 	.mknod		= ramfs_mknod,
 	.rename		= simple_rename,
+	.tmpfile	= ramfs_tmpfile,
 };
 
 /*
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index d7f54e535294..f18e6e828b21 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -1460,7 +1460,8 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
 			start = vma->vm_start;
 		vma_end = min(end, vma->vm_end);
 
-		new_flags = (vma->vm_flags & ~vm_flags) | vm_flags;
+		new_flags = (vma->vm_flags &
+			     ~(VM_UFFD_MISSING|VM_UFFD_WP)) | vm_flags;
 		prev = vma_merge(mm, prev, start, vma_end, new_flags,
 				 vma->anon_vma, vma->vm_file, vma->vm_pgoff,
 				 vma_policy(vma),
diff --git a/include/asm-generic/4level-fixup.h b/include/asm-generic/4level-fixup.h
index e3667c9a33a5..c86cf7cb4bba 100644
--- a/include/asm-generic/4level-fixup.h
+++ b/include/asm-generic/4level-fixup.h
@@ -30,7 +30,6 @@
 #undef pud_free_tlb
 #define pud_free_tlb(tlb, x, addr)	do { } while (0)
 #define pud_free(mm, x)			do { } while (0)
-#define __pud_free_tlb(tlb, x, addr)	do { } while (0)
 
 #undef  pud_addr_end
 #define pud_addr_end(addr, end)		(end)
diff --git a/include/asm-generic/5level-fixup.h b/include/asm-generic/5level-fixup.h
index f6947da70d71..4c74b1c1d13b 100644
--- a/include/asm-generic/5level-fixup.h
+++ b/include/asm-generic/5level-fixup.h
@@ -51,7 +51,6 @@ static inline int p4d_present(p4d_t p4d)
 #undef p4d_free_tlb
 #define p4d_free_tlb(tlb, x, addr)	do { } while (0)
 #define p4d_free(mm, x)			do { } while (0)
-#define __p4d_free_tlb(tlb, x, addr)	do { } while (0)
 
 #undef  p4d_addr_end
 #define p4d_addr_end(addr, end)		(end)
diff --git a/include/asm-generic/pgtable-nop4d.h b/include/asm-generic/pgtable-nop4d.h
index aebab905e6cd..ce2cbb3c380f 100644
--- a/include/asm-generic/pgtable-nop4d.h
+++ b/include/asm-generic/pgtable-nop4d.h
@@ -50,7 +50,7 @@ static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
  */
 #define p4d_alloc_one(mm, address)		NULL
 #define p4d_free(mm, x)				do { } while (0)
-#define __p4d_free_tlb(tlb, x, a)		do { } while (0)
+#define p4d_free_tlb(tlb, x, a)			do { } while (0)
 
 #undef  p4d_addr_end
 #define p4d_addr_end(addr, end)			(end)
diff --git a/include/asm-generic/pgtable-nopmd.h b/include/asm-generic/pgtable-nopmd.h
index b85b8271a73d..0d9b28cba16d 100644
--- a/include/asm-generic/pgtable-nopmd.h
+++ b/include/asm-generic/pgtable-nopmd.h
@@ -60,7 +60,7 @@ static inline pmd_t * pmd_offset(pud_t * pud, unsigned long address)
 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
 {
 }
-#define __pmd_free_tlb(tlb, x, a)		do { } while (0)
+#define pmd_free_tlb(tlb, x, a)		do { } while (0)
 
 #undef  pmd_addr_end
 #define pmd_addr_end(addr, end)			(end)
diff --git a/include/asm-generic/pgtable-nopud.h b/include/asm-generic/pgtable-nopud.h
index c77a1d301155..d3776cb494c0 100644
--- a/include/asm-generic/pgtable-nopud.h
+++ b/include/asm-generic/pgtable-nopud.h
@@ -59,7 +59,7 @@ static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
  */
 #define pud_alloc_one(mm, address)		NULL
 #define pud_free(mm, x)				do { } while (0)
-#define __pud_free_tlb(tlb, x, a)		do { } while (0)
+#define pud_free_tlb(tlb, x, a)		        do { } while (0)
 
 #undef  pud_addr_end
 #define pud_addr_end(addr, end)			(end)
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 818691846c90..9cdcbc7c0b7b 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -558,8 +558,19 @@ static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot)
  * Do the tests inline, but report and clear the bad entry in mm/memory.c.
  */
 void pgd_clear_bad(pgd_t *);
+
+#ifndef __PAGETABLE_P4D_FOLDED
 void p4d_clear_bad(p4d_t *);
+#else
+#define p4d_clear_bad(p4d)        do { } while (0)
+#endif
+
+#ifndef __PAGETABLE_PUD_FOLDED
 void pud_clear_bad(pud_t *);
+#else
+#define pud_clear_bad(p4d)        do { } while (0)
+#endif
+
 void pmd_clear_bad(pmd_t *);
 
 static inline int pgd_none_or_clear_bad(pgd_t *pgd)
diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h
index 04c0644006fd..05dddc17522b 100644
--- a/include/asm-generic/tlb.h
+++ b/include/asm-generic/tlb.h
@@ -584,7 +584,6 @@ static inline void tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vm
 	} while (0)
 #endif
 
-#ifndef __ARCH_HAS_4LEVEL_HACK
 #ifndef pud_free_tlb
 #define pud_free_tlb(tlb, pudp, address)			\
 	do {							\
@@ -594,9 +593,7 @@ static inline void tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vm
 		__pud_free_tlb(tlb, pudp, address);		\
 	} while (0)
 #endif
-#endif
 
-#ifndef __ARCH_HAS_5LEVEL_HACK
 #ifndef p4d_free_tlb
 #define p4d_free_tlb(tlb, pudp, address)			\
 	do {							\
@@ -605,7 +602,6 @@ static inline void tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vm
 		__p4d_free_tlb(tlb, pudp, address);		\
 	} while (0)
 #endif
-#endif
 
 #endif /* CONFIG_MMU */
 
diff --git a/include/linux/build_bug.h b/include/linux/build_bug.h
index 0fe5426f2bdc..e3a0be2c90ad 100644
--- a/include/linux/build_bug.h
+++ b/include/linux/build_bug.h
@@ -9,11 +9,11 @@
 #else /* __CHECKER__ */
 /*
  * Force a compilation error if condition is true, but also produce a
- * result (of value 0 and type size_t), so the expression can be used
+ * result (of value 0 and type int), so the expression can be used
  * e.g. in a structure initializer (or where-ever else comma expressions
  * aren't permitted).
  */
-#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:(-!!(e)); }))
+#define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
 #endif /* __CHECKER__ */
 
 /* Force a compilation error if a constant expression is not a power of 2 */
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 61f2f6ff9467..e5b817cb86e7 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -612,6 +612,8 @@ static inline bool pm_suspended_storage(void)
 /* The below functions must be run on a range from a single zone. */
 extern int alloc_contig_range(unsigned long start, unsigned long end,
 			      unsigned migratetype, gfp_t gfp_mask);
+extern struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask,
+				       int nid, nodemask_t *nodemask);
 #endif
 void free_contig_range(unsigned long pfn, unsigned int nr_pages);
 
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 53fc34f930d0..4c5a16be7912 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -105,8 +105,7 @@ void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason);
 void free_huge_page(struct page *page);
 void hugetlb_fix_reserve_counts(struct inode *inode);
 extern struct mutex *hugetlb_fault_mutex_table;
-u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
-				pgoff_t idx, unsigned long address);
+u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx);
 
 pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud);
 
diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index f491690d54c6..b38bbefabfab 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -358,6 +358,9 @@ static inline phys_addr_t memblock_phys_alloc(phys_addr_t size,
 					 MEMBLOCK_ALLOC_ACCESSIBLE);
 }
 
+void *memblock_alloc_exact_nid_raw(phys_addr_t size, phys_addr_t align,
+				 phys_addr_t min_addr, phys_addr_t max_addr,
+				 int nid);
 void *memblock_alloc_try_nid_raw(phys_addr_t size, phys_addr_t align,
 				 phys_addr_t min_addr, phys_addr_t max_addr,
 				 int nid);
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index ae703ea3ef48..e82928deea88 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -58,7 +58,6 @@ enum mem_cgroup_protection {
 
 struct mem_cgroup_reclaim_cookie {
 	pg_data_t *pgdat;
-	int priority;
 	unsigned int generation;
 };
 
@@ -112,7 +111,7 @@ struct memcg_shrinker_map {
 };
 
 /*
- * per-zone information in memory controller.
+ * per-node information in memory controller.
  */
 struct mem_cgroup_per_node {
 	struct lruvec		lruvec;
@@ -126,7 +125,7 @@ struct mem_cgroup_per_node {
 
 	unsigned long		lru_zone_size[MAX_NR_ZONES][NR_LRU_LISTS];
 
-	struct mem_cgroup_reclaim_iter	iter[DEF_PRIORITY + 1];
+	struct mem_cgroup_reclaim_iter	iter;
 
 	struct memcg_shrinker_map __rcu	*shrinker_map;
 
@@ -399,8 +398,7 @@ mem_cgroup_nodeinfo(struct mem_cgroup *memcg, int nid)
  * @memcg: memcg of the wanted lruvec
  *
  * Returns the lru list vector holding pages for a given @node or a given
- * @memcg and @zone. This can be the node lruvec, if the memory controller
- * is disabled.
+ * @memcg. This can be the node lruvec, if the memory controller is disabled.
  */
 static inline struct lruvec *mem_cgroup_lruvec(struct pglist_data *pgdat,
 				struct mem_cgroup *memcg)
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index f46ea71b4ffd..384ffb3d69ab 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -102,13 +102,10 @@ extern unsigned long __offline_isolated_pages(unsigned long start_pfn,
 
 typedef void (*online_page_callback_t)(struct page *page, unsigned int order);
 
+extern void generic_online_page(struct page *page, unsigned int order);
 extern int set_online_page_callback(online_page_callback_t callback);
 extern int restore_online_page_callback(online_page_callback_t callback);
 
-extern void __online_page_set_limits(struct page *page);
-extern void __online_page_increment_counters(struct page *page);
-extern void __online_page_free(struct page *page);
-
 extern int try_online_node(int nid);
 
 extern int arch_add_memory(int nid, u64 start, u64 size,
@@ -125,8 +122,8 @@ static inline bool movable_node_is_enabled(void)
 
 extern void arch_remove_memory(int nid, u64 start, u64 size,
 			       struct vmem_altmap *altmap);
-extern void __remove_pages(struct zone *zone, unsigned long start_pfn,
-			   unsigned long nr_pages, struct vmem_altmap *altmap);
+extern void __remove_pages(unsigned long start_pfn, unsigned long nr_pages,
+			   struct vmem_altmap *altmap);
 
 /* reasonably generic interface to expand the physical pages */
 extern int __add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
@@ -345,6 +342,9 @@ extern int add_memory(int nid, u64 start, u64 size);
 extern int add_memory_resource(int nid, struct resource *resource);
 extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn,
 		unsigned long nr_pages, struct vmem_altmap *altmap);
+extern void remove_pfn_range_from_zone(struct zone *zone,
+				       unsigned long start_pfn,
+				       unsigned long nr_pages);
 extern bool is_memblock_offlined(struct memory_block *mem);
 extern int sparse_add_section(int nid, unsigned long pfn,
 		unsigned long nr_pages, struct vmem_altmap *altmap);
diff --git a/include/linux/memremap.h b/include/linux/memremap.h
index 6fefb09af7c3..c676e33205d3 100644
--- a/include/linux/memremap.h
+++ b/include/linux/memremap.h
@@ -123,6 +123,7 @@ static inline struct vmem_altmap *pgmap_altmap(struct dev_pagemap *pgmap)
 }
 
 #ifdef CONFIG_ZONE_DEVICE
+bool pfn_zone_device_reserved(unsigned long pfn);
 void *memremap_pages(struct dev_pagemap *pgmap, int nid);
 void memunmap_pages(struct dev_pagemap *pgmap);
 void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap);
@@ -133,6 +134,11 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
 unsigned long vmem_altmap_offset(struct vmem_altmap *altmap);
 void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns);
 #else
+static inline bool pfn_zone_device_reserved(unsigned long pfn)
+{
+	return false;
+}
+
 static inline void *devm_memremap_pages(struct device *dev,
 		struct dev_pagemap *pgmap)
 {
diff --git a/include/linux/mm.h b/include/linux/mm.h
index cc292273e6ba..82e4aaa8bef9 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1648,19 +1648,27 @@ static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
 	return (unsigned long)val;
 }
 
+void mm_trace_rss_stat(int member, long count);
+
 static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
 {
-	atomic_long_add(value, &mm->rss_stat.count[member]);
+	long count = atomic_long_add_return(value, &mm->rss_stat.count[member]);
+
+	mm_trace_rss_stat(member, count);
 }
 
 static inline void inc_mm_counter(struct mm_struct *mm, int member)
 {
-	atomic_long_inc(&mm->rss_stat.count[member]);
+	long count = atomic_long_inc_return(&mm->rss_stat.count[member]);
+
+	mm_trace_rss_stat(member, count);
 }
 
 static inline void dec_mm_counter(struct mm_struct *mm, int member)
 {
-	atomic_long_dec(&mm->rss_stat.count[member]);
+	long count = atomic_long_dec_return(&mm->rss_stat.count[member]);
+
+	mm_trace_rss_stat(member, count);
 }
 
 /* Optimized variant when page is already known not to be PageAnon */
@@ -2219,9 +2227,6 @@ void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...);
 
 extern void setup_per_cpu_pageset(void);
 
-extern void zone_pcp_update(struct zone *zone);
-extern void zone_pcp_reset(struct zone *zone);
-
 /* page_alloc.c */
 extern int min_free_kbytes;
 extern int watermark_boost_factor;
@@ -2786,7 +2791,7 @@ extern int sysctl_memory_failure_early_kill;
 extern int sysctl_memory_failure_recovery;
 extern void shake_page(struct page *p, int access);
 extern atomic_long_t num_poisoned_pages __read_mostly;
-extern int soft_offline_page(struct page *page, int flags);
+extern int soft_offline_page(unsigned long pfn, int flags);
 
 
 /*
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index b0a36d1580b6..d4ca03b93373 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1079,7 +1079,7 @@ static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
 /**
  * for_each_zone_zonelist_nodemask - helper macro to iterate over valid zones in a zonelist at or below a given zone index and within a nodemask
  * @zone - The current zone in the iterator
- * @z - The current pointer within zonelist->zones being iterated
+ * @z - The current pointer within zonelist->_zonerefs being iterated
  * @zlist - The zonelist being iterated
  * @highidx - The zone index of the highest zone to return
  * @nodemask - Nodemask allowed by the allocator
diff --git a/include/linux/notifier.h b/include/linux/notifier.h
index 0096a05395e3..018947611483 100644
--- a/include/linux/notifier.h
+++ b/include/linux/notifier.h
@@ -150,10 +150,6 @@ extern int raw_notifier_chain_register(struct raw_notifier_head *nh,
 extern int srcu_notifier_chain_register(struct srcu_notifier_head *nh,
 		struct notifier_block *nb);
 
-extern int blocking_notifier_chain_cond_register(
-		struct blocking_notifier_head *nh,
-		struct notifier_block *nb);
-
 extern int atomic_notifier_chain_unregister(struct atomic_notifier_head *nh,
 		struct notifier_block *nb);
 extern int blocking_notifier_chain_unregister(struct blocking_notifier_head *nh,
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index f91cb8898ff0..3b8e5c5f7e1f 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -610,27 +610,6 @@ static inline int PageTransCompound(struct page *page)
 }
 
 /*
- * PageTransCompoundMap is the same as PageTransCompound, but it also
- * guarantees the primary MMU has the entire compound page mapped
- * through pmd_trans_huge, which in turn guarantees the secondary MMUs
- * can also map the entire compound page. This allows the secondary
- * MMUs to call get_user_pages() only once for each compound page and
- * to immediately map the entire compound page with a single secondary
- * MMU fault. If there will be a pmd split later, the secondary MMUs
- * will get an update through the MMU notifier invalidation through
- * split_huge_pmd().
- *
- * Unlike PageTransCompound, this is safe to be called only while
- * split_huge_pmd() cannot run from under us, like if protected by the
- * MMU notifier, otherwise it may result in page->_mapcount < 0 false
- * positives.
- */
-static inline int PageTransCompoundMap(struct page *page)
-{
-	return PageTransCompound(page) && atomic_read(&page->_mapcount) < 0;
-}
-
-/*
  * PageTransTail returns true for both transparent huge pages
  * and hugetlbfs pages, so it should only be called when it's known
  * that hugetlbfs pages aren't involved.
@@ -681,6 +660,39 @@ static inline int TestClearPageDoubleMap(struct page *page)
 	return test_and_clear_bit(PG_double_map, &page[1].flags);
 }
 
+/*
+ * PageTransCompoundMap is the same as PageTransCompound, but it also
+ * guarantees the primary MMU has the entire compound page mapped
+ * through pmd_trans_huge, which in turn guarantees the secondary MMUs
+ * can also map the entire compound page. This allows the secondary
+ * MMUs to call get_user_pages() only once for each compound page and
+ * to immediately map the entire compound page with a single secondary
+ * MMU fault. If there will be a pmd split later, the secondary MMUs
+ * will get an update through the MMU notifier invalidation through
+ * split_huge_pmd().
+ *
+ * Unlike PageTransCompound, this is safe to be called only while
+ * split_huge_pmd() cannot run from under us, like if protected by the
+ * MMU notifier, otherwise it may result in page->_mapcount check false
+ * positives.
+ *
+ * We have to treat page cache THP differently since every subpage of it
+ * would get _mapcount inc'ed once it is PMD mapped.  But, it may be PTE
+ * mapped in the current process so checking PageDoubleMap flag to rule
+ * this out.
+ */
+static inline int PageTransCompoundMap(struct page *page)
+{
+	bool pmd_mapped;
+
+	if (PageAnon(page))
+		pmd_mapped = atomic_read(&page->_mapcount) < 0;
+	else
+		pmd_mapped = atomic_read(&page->_mapcount) >= 0 &&
+			     !PageDoubleMap(compound_head(page));
+
+	return PageTransCompound(page) && pmd_mapped;
+}
 #else
 TESTPAGEFLAG_FALSE(TransHuge)
 TESTPAGEFLAG_FALSE(TransCompound)
diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
index 1099c2fee20f..6861df759fad 100644
--- a/include/linux/page-isolation.h
+++ b/include/linux/page-isolation.h
@@ -30,7 +30,7 @@ static inline bool is_migrate_isolate(int migratetype)
 }
 #endif
 
-#define SKIP_HWPOISON	0x1
+#define MEMORY_OFFLINE	0x1
 #define REPORT_FAILURE	0x2
 
 bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
@@ -58,7 +58,7 @@ undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
  * Test all pages in [start_pfn, end_pfn) are isolated or not.
  */
 int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
-			bool skip_hwpoisoned_pages);
+			int isol_flags);
 
 struct page *alloc_migrate_target(struct page *page, unsigned long private);
 
diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
index a705aa2d03f9..0640be56dcbd 100644
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -58,8 +58,8 @@ extern int remove_proc_subtree(const char *, struct proc_dir_entry *);
 struct proc_dir_entry *proc_create_net_data(const char *name, umode_t mode,
 		struct proc_dir_entry *parent, const struct seq_operations *ops,
 		unsigned int state_size, void *data);
-#define proc_create_net(name, mode, parent, state_size, ops) \
-	proc_create_net_data(name, mode, parent, state_size, ops, NULL)
+#define proc_create_net(name, mode, parent, ops, state_size) \
+	proc_create_net_data(name, mode, parent, ops, state_size, NULL)
 struct proc_dir_entry *proc_create_net_single(const char *name, umode_t mode,
 		struct proc_dir_entry *parent,
 		int (*show)(struct seq_file *, void *), void *data);
diff --git a/include/linux/sched.h b/include/linux/sched.h
index f72984f94a5c..d6c80e7991df 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -905,6 +905,7 @@ struct task_struct {
 #ifdef CONFIG_DETECT_HUNG_TASK
 	unsigned long			last_switch_count;
 	unsigned long			last_switch_time;
+	unsigned long			killed_time;
 #endif
 	/* Filesystem information: */
 	struct fs_struct		*fs;
@@ -1251,6 +1252,7 @@ struct task_struct {
 #ifdef CONFIG_MMU
 	struct task_struct		*oom_reaper_list;
 #endif
+	struct list_head		oom_victim_list;
 #ifdef CONFIG_VMAP_STACK
 	struct vm_struct		*stack_vm_area;
 #endif
@@ -1271,6 +1273,13 @@ struct task_struct {
 	unsigned long			prev_lowest_stack;
 #endif
 
+#ifdef CONFIG_DEBUG_AID_FOR_SYZBOT
+	unsigned long			getblk_stamp;
+	unsigned int			getblk_executed;
+	unsigned int			getblk_bh_count;
+	unsigned long			getblk_bh_state;
+#endif
+
 	/*
 	 * New fields for task_struct should be added above here, so that
 	 * they are included in the randomized portion of task_struct.
diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h
index d4f6215ee03f..89f55e914673 100644
--- a/include/linux/sched/sysctl.h
+++ b/include/linux/sched/sysctl.h
@@ -12,6 +12,7 @@ extern unsigned int  sysctl_hung_task_panic;
 extern unsigned long sysctl_hung_task_timeout_secs;
 extern unsigned long sysctl_hung_task_check_interval_secs;
 extern int sysctl_hung_task_warnings;
+extern int sysctl_hung_task_interval_warnings;
 extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
 					 void __user *buffer,
 					 size_t *lenp, loff_t *ppos);
diff --git a/include/linux/slab.h b/include/linux/slab.h
index 6d52953dbdf0..270f03ee3f83 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -561,26 +561,6 @@ static __always_inline void *kmalloc(size_t size, gfp_t flags)
 	return __kmalloc(size, flags);
 }
 
-/*
- * Determine size used for the nth kmalloc cache.
- * return size or 0 if a kmalloc cache for that
- * size does not exist
- */
-static __always_inline unsigned int kmalloc_size(unsigned int n)
-{
-#ifndef CONFIG_SLOB
-	if (n > 2)
-		return 1U << n;
-
-	if (n == 1 && KMALLOC_MIN_SIZE <= 32)
-		return 96;
-
-	if (n == 2 && KMALLOC_MIN_SIZE <= 64)
-		return 192;
-#endif
-	return 0;
-}
-
 static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 {
 #ifndef CONFIG_SLOB
diff --git a/include/linux/string.h b/include/linux/string.h
index b6ccdc2c7f02..f516cec5277c 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -35,6 +35,51 @@ ssize_t strscpy(char *, const char *, size_t);
 /* Wraps calls to strscpy()/memset(), no arch specific code required */
 ssize_t strscpy_pad(char *dest, const char *src, size_t count);
 
+/**
+ * stracpy - Copy a C-string into an array of char/u8/s8 or equivalent
+ * @dest: Where to copy the string, must be an array of char and not a pointer
+ * @src: String to copy, may be a pointer or const char array
+ *
+ * Helper for strscpy().
+ * Copies a maximum of sizeof(@dest) bytes of @src with %NUL termination.
+ *
+ * Returns:
+ * * The number of characters copied (not including the trailing %NUL)
+ * * -E2BIG if @dest is a zero size array or @src was truncated.
+ */
+#define stracpy(dest, src)						\
+({									\
+	size_t count = ARRAY_SIZE(dest);				\
+	BUILD_BUG_ON(!(__same_type(dest, char[]) ||			\
+		       __same_type(dest, unsigned char[]) ||		\
+		       __same_type(dest, signed char[])));		\
+									\
+	strscpy(dest, src, count);					\
+})
+
+/**
+ * stracpy_pad - Copy a C-string into an array of char/u8/s8 with %NUL padding
+ * @dest: Where to copy the string, must be an array of char and not a pointer
+ * @src: String to copy, may be a pointer or const char array
+ *
+ * Helper for strscpy_pad().
+ * Copies a maximum of sizeof(@dest) bytes of @src with %NUL termination
+ * and zero-pads the remaining size of @dest
+ *
+ * Returns:
+ * * The number of characters copied (not including the trailing %NUL)
+ * * -E2BIG if @dest is a zero size array or @src was truncated.
+ */
+#define stracpy_pad(dest, src)						\
+({									\
+	size_t count = ARRAY_SIZE(dest);				\
+	BUILD_BUG_ON(!(__same_type(dest, char[]) ||			\
+		       __same_type(dest, unsigned char[]) ||		\
+		       __same_type(dest, signed char[])));		\
+									\
+	strscpy_pad(dest, src, count);					\
+})
+
 #ifndef __HAVE_ARCH_STRCAT
 extern char * strcat(char *, const char *);
 #endif
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index 6df477329b76..02fa84493f23 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -120,8 +120,7 @@ static inline void *proc_sys_poll_event(struct ctl_table_poll *poll)
 	struct ctl_table_poll name = __CTL_TABLE_POLL_INITIALIZER(name)
 
 /* A sysctl table is an array of struct ctl_table: */
-struct ctl_table 
-{
+struct ctl_table {
 	const char *procname;		/* Text ID for /proc/sys, or zero */
 	void *data;
 	int maxlen;
@@ -140,8 +139,7 @@ struct ctl_node {
 
 /* struct ctl_table_header is used to maintain dynamic lists of
    struct ctl_table trees. */
-struct ctl_table_header
-{
+struct ctl_table_header {
 	union {
 		struct {
 			struct ctl_table *ctl_table;
diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h
index 659a4400517b..e93e249a4e9b 100644
--- a/include/linux/thread_info.h
+++ b/include/linux/thread_info.h
@@ -147,6 +147,8 @@ check_copy_size(const void *addr, size_t bytes, bool is_source)
 			__bad_copy_to();
 		return false;
 	}
+	if (WARN_ON_ONCE(bytes > INT_MAX))
+		return false;
 	check_object_size(addr, bytes, is_source);
 	return true;
 }
diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
index bdeda4b079fe..292485f3d24d 100644
--- a/include/linux/vmstat.h
+++ b/include/linux/vmstat.h
@@ -31,6 +31,12 @@ struct reclaim_stat {
 	unsigned nr_unmap_fail;
 };
 
+enum writeback_stat_item {
+	NR_DIRTY_THRESHOLD,
+	NR_DIRTY_BG_THRESHOLD,
+	NR_VM_WRITEBACK_STAT_ITEMS,
+};
+
 #ifdef CONFIG_VM_EVENT_COUNTERS
 /*
  * Light weight per cpu counter implementation.
@@ -381,4 +387,48 @@ static inline void __mod_zone_freepage_state(struct zone *zone, int nr_pages,
 
 extern const char * const vmstat_text[];
 
+static inline const char *zone_stat_name(enum zone_stat_item item)
+{
+	return vmstat_text[item];
+}
+
+#ifdef CONFIG_NUMA
+static inline const char *numa_stat_name(enum numa_stat_item item)
+{
+	return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
+			   item];
+}
+#endif /* CONFIG_NUMA */
+
+static inline const char *node_stat_name(enum node_stat_item item)
+{
+	return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
+			   NR_VM_NUMA_STAT_ITEMS +
+			   item];
+}
+
+static inline const char *lru_list_name(enum lru_list lru)
+{
+	return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
+}
+
+static inline const char *writeback_stat_name(enum writeback_stat_item item)
+{
+	return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
+			   NR_VM_NUMA_STAT_ITEMS +
+			   NR_VM_NODE_STAT_ITEMS +
+			   item];
+}
+
+#if defined(CONFIG_VM_EVENT_COUNTERS) || defined(CONFIG_MEMCG)
+static inline const char *vm_event_name(enum vm_event_item item)
+{
+	return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
+			   NR_VM_NUMA_STAT_ITEMS +
+			   NR_VM_NODE_STAT_ITEMS +
+			   NR_VM_WRITEBACK_STAT_ITEMS +
+			   item];
+}
+#endif /* CONFIG_VM_EVENT_COUNTERS || CONFIG_MEMCG */
+
 #endif /* _LINUX_VMSTAT_H */
diff --git a/include/linux/wait.h b/include/linux/wait.h
index 3eb7cae8206c..3647d1008d88 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -540,7 +540,7 @@ do {										\
 ({										\
 	int __ret = 0;								\
 	might_sleep();								\
-	if (!(condition))							\
+	if (!(condition) && (timeout))						\
 		__ret = __wait_event_hrtimeout(wq_head, condition, timeout,	\
 					       TASK_UNINTERRUPTIBLE);		\
 	__ret;									\
@@ -566,7 +566,7 @@ do {										\
 ({										\
 	long __ret = 0;								\
 	might_sleep();								\
-	if (!(condition))							\
+	if (!(condition) && (timeout))						\
 		__ret = __wait_event_hrtimeout(wq, condition, timeout,		\
 					       TASK_INTERRUPTIBLE);		\
 	__ret;									\
diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h
index 69e8bb8963db..5a0666bfcf85 100644
--- a/include/trace/events/kmem.h
+++ b/include/trace/events/kmem.h
@@ -316,6 +316,27 @@ TRACE_EVENT(mm_page_alloc_extfrag,
 		__entry->change_ownership)
 );
 
+TRACE_EVENT(rss_stat,
+
+	TP_PROTO(int member,
+		long count),
+
+	TP_ARGS(member, count),
+
+	TP_STRUCT__entry(
+		__field(int, member)
+		__field(long, size)
+	),
+
+	TP_fast_assign(
+		__entry->member = member;
+		__entry->size = (count << PAGE_SHIFT);
+	),
+
+	TP_printk("member=%d size=%ldB",
+		__entry->member,
+		__entry->size)
+	);
 #endif /* _TRACE_KMEM_H */
 
 /* This part must be outside protection */
diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index a5ab2973e8dc..c37e2280e6dd 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -127,18 +127,43 @@ DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_direct_reclaim_b
 );
 
 #ifdef CONFIG_MEMCG
-DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_memcg_reclaim_begin,
+DECLARE_EVENT_CLASS(mm_vmscan_memcg_reclaim_begin_template,
 
-	TP_PROTO(int order, gfp_t gfp_flags),
+	TP_PROTO(unsigned int cgroup_ino, int order, gfp_t gfp_flags),
 
-	TP_ARGS(order, gfp_flags)
+	TP_ARGS(cgroup_ino, order, gfp_flags),
+
+	TP_STRUCT__entry(
+		__field(unsigned int, cgroup_ino)
+		__field(int, order)
+		__field(gfp_t, gfp_flags)
+	),
+
+	TP_fast_assign(
+		__entry->cgroup_ino	= cgroup_ino;
+		__entry->order		= order;
+		__entry->gfp_flags	= gfp_flags;
+	),
+
+	TP_printk("cgroup_ino=%u order=%d gfp_flags=%s",
+		__entry->cgroup_ino, __entry->order,
+		show_gfp_flags(__entry->gfp_flags))
 );
 
-DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_memcg_softlimit_reclaim_begin,
+DEFINE_EVENT(mm_vmscan_memcg_reclaim_begin_template,
+	     mm_vmscan_memcg_reclaim_begin,
 
-	TP_PROTO(int order, gfp_t gfp_flags),
+	TP_PROTO(unsigned int cgroup_ino, int order, gfp_t gfp_flags),
 
-	TP_ARGS(order, gfp_flags)
+	TP_ARGS(cgroup_ino, order, gfp_flags)
+);
+
+DEFINE_EVENT(mm_vmscan_memcg_reclaim_begin_template,
+	     mm_vmscan_memcg_softlimit_reclaim_begin,
+
+	TP_PROTO(unsigned int cgroup_ino, int order, gfp_t gfp_flags),
+
+	TP_ARGS(cgroup_ino, order, gfp_flags)
 );
 #endif /* CONFIG_MEMCG */
 
@@ -167,18 +192,40 @@ DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_direct_reclaim_end
 );
 
 #ifdef CONFIG_MEMCG
-DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_memcg_reclaim_end,
+DECLARE_EVENT_CLASS(mm_vmscan_memcg_reclaim_end_template,
 
-	TP_PROTO(unsigned long nr_reclaimed),
+	TP_PROTO(unsigned int cgroup_ino, unsigned long nr_reclaimed),
 
-	TP_ARGS(nr_reclaimed)
+	TP_ARGS(cgroup_ino, nr_reclaimed),
+
+	TP_STRUCT__entry(
+		__field(unsigned int, cgroup_ino)
+		__field(unsigned long, nr_reclaimed)
+	),
+
+	TP_fast_assign(
+		__entry->cgroup_ino	= cgroup_ino;
+		__entry->nr_reclaimed	= nr_reclaimed;
+	),
+
+	TP_printk("cgroup_ino=%u nr_reclaimed=%lu",
+		__entry->cgroup_ino, __entry->nr_reclaimed)
 );
 
-DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_memcg_softlimit_reclaim_end,
+DEFINE_EVENT(mm_vmscan_memcg_reclaim_end_template,
+	     mm_vmscan_memcg_reclaim_end,
 
-	TP_PROTO(unsigned long nr_reclaimed),
+	TP_PROTO(unsigned int cgroup_ino, unsigned long nr_reclaimed),
 
-	TP_ARGS(nr_reclaimed)
+	TP_ARGS(cgroup_ino, nr_reclaimed)
+);
+
+DEFINE_EVENT(mm_vmscan_memcg_reclaim_end_template,
+	     mm_vmscan_memcg_softlimit_reclaim_end,
+
+	TP_PROTO(unsigned int cgroup_ino, unsigned long nr_reclaimed),
+
+	TP_ARGS(cgroup_ino, nr_reclaimed)
 );
 #endif /* CONFIG_MEMCG */
 
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 3d920ff15c80..49a05ba3000d 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -63,6 +63,66 @@ struct posix_msg_tree_node {
 	int			priority;
 };
 
+/*
+ * Locking:
+ *
+ * Accesses to a message queue are synchronized by acquiring info->lock.
+ *
+ * There are two notable exceptions:
+ * - The actual wakeup of a sleeping task is performed using the wake_q
+ *   framework. info->lock is already released when wake_up_q is called.
+ * - The exit codepaths after sleeping check ext_wait_queue->state without
+ *   any locks. If it is STATE_READY, then the syscall is completed without
+ *   acquiring info->lock.
+ *
+ * MQ_BARRIER:
+ * To achieve proper release/acquire memory barrier pairing, the state is set to
+ * STATE_READY with smp_store_release(), and it is read with READ_ONCE followed
+ * by smp_acquire__after_ctrl_dep(). In addition, wake_q_add_safe() is used.
+ *
+ * This prevents the following races:
+ *
+ * 1) With the simple wake_q_add(), the task could be gone already before
+ *    the increase of the reference happens
+ * Thread A
+ *				Thread B
+ * WRITE_ONCE(wait.state, STATE_NONE);
+ * schedule_hrtimeout()
+ *				wake_q_add(A)
+ *				if (cmpxchg()) // success
+ *				   ->state = STATE_READY (reordered)
+ * <timeout returns>
+ * if (wait.state == STATE_READY) return;
+ * sysret to user space
+ * sys_exit()
+ *				get_task_struct() // UaF
+ *
+ * Solution: Use wake_q_add_safe() and perform the get_task_struct() before
+ * the smp_store_release() that does ->state = STATE_READY.
+ *
+ * 2) Without proper _release/_acquire barriers, the woken up task
+ *    could read stale data
+ *
+ * Thread A
+ *				Thread B
+ * do_mq_timedreceive
+ * WRITE_ONCE(wait.state, STATE_NONE);
+ * schedule_hrtimeout()
+ *				state = STATE_READY;
+ * <timeout returns>
+ * if (wait.state == STATE_READY) return;
+ * msg_ptr = wait.msg;		// Access to stale data!
+ *				receiver->msg = message; (reordered)
+ *
+ * Solution: use _release and _acquire barriers.
+ *
+ * 3) There is intentionally no barrier when setting current->state
+ *    to TASK_INTERRUPTIBLE: spin_unlock(&info->lock) provides the
+ *    release memory barrier, and the wakeup is triggered when holding
+ *    info->lock, i.e. spin_lock(&info->lock) provided a pairing
+ *    acquire memory barrier.
+ */
+
 struct ext_wait_queue {		/* queue of sleeping tasks */
 	struct task_struct *task;
 	struct list_head list;
@@ -646,18 +706,23 @@ static int wq_sleep(struct mqueue_inode_info *info, int sr,
 	wq_add(info, sr, ewp);
 
 	for (;;) {
+		/* memory barrier not required, we hold info->lock */
 		__set_current_state(TASK_INTERRUPTIBLE);
 
 		spin_unlock(&info->lock);
 		time = schedule_hrtimeout_range_clock(timeout, 0,
 			HRTIMER_MODE_ABS, CLOCK_REALTIME);
 
-		if (ewp->state == STATE_READY) {
+		if (READ_ONCE(ewp->state) == STATE_READY) {
+			/* see MQ_BARRIER for purpose/pairing */
+			smp_acquire__after_ctrl_dep();
 			retval = 0;
 			goto out;
 		}
 		spin_lock(&info->lock);
-		if (ewp->state == STATE_READY) {
+
+		/* we hold info->lock, so no memory barrier required */
+		if (READ_ONCE(ewp->state) == STATE_READY) {
 			retval = 0;
 			goto out_unlock;
 		}
@@ -918,6 +983,18 @@ out_name:
  * The same algorithm is used for senders.
  */
 
+static inline void __pipelined_op(struct wake_q_head *wake_q,
+				  struct mqueue_inode_info *info,
+				  struct ext_wait_queue *this)
+{
+	list_del(&this->list);
+	get_task_struct(this->task);
+
+	/* see MQ_BARRIER for purpose/pairing */
+	smp_store_release(&this->state, STATE_READY);
+	wake_q_add_safe(wake_q, this->task);
+}
+
 /* pipelined_send() - send a message directly to the task waiting in
  * sys_mq_timedreceive() (without inserting message into a queue).
  */
@@ -927,17 +1004,7 @@ static inline void pipelined_send(struct wake_q_head *wake_q,
 				  struct ext_wait_queue *receiver)
 {
 	receiver->msg = message;
-	list_del(&receiver->list);
-	wake_q_add(wake_q, receiver->task);
-	/*
-	 * Rely on the implicit cmpxchg barrier from wake_q_add such
-	 * that we can ensure that updating receiver->state is the last
-	 * write operation: As once set, the receiver can continue,
-	 * and if we don't have the reference count from the wake_q,
-	 * yet, at that point we can later have a use-after-free
-	 * condition and bogus wakeup.
-	 */
-	receiver->state = STATE_READY;
+	__pipelined_op(wake_q, info, receiver);
 }
 
 /* pipelined_receive() - if there is task waiting in sys_mq_timedsend()
@@ -955,9 +1022,7 @@ static inline void pipelined_receive(struct wake_q_head *wake_q,
 	if (msg_insert(sender->msg, info))
 		return;
 
-	list_del(&sender->list);
-	wake_q_add(wake_q, sender->task);
-	sender->state = STATE_READY;
+	__pipelined_op(wake_q, info, sender);
 }
 
 static int do_mq_timedsend(mqd_t mqdes, const char __user *u_msg_ptr,
@@ -1044,7 +1109,9 @@ static int do_mq_timedsend(mqd_t mqdes, const char __user *u_msg_ptr,
 		} else {
 			wait.task = current;
 			wait.msg = (void *) msg_ptr;
-			wait.state = STATE_NONE;
+
+			/* memory barrier not required, we hold info->lock */
+			WRITE_ONCE(wait.state, STATE_NONE);
 			ret = wq_sleep(info, SEND, timeout, &wait);
 			/*
 			 * wq_sleep must be called with info->lock held, and
@@ -1147,7 +1214,9 @@ static int do_mq_timedreceive(mqd_t mqdes, char __user *u_msg_ptr,
 			ret = -EAGAIN;
 		} else {
 			wait.task = current;
-			wait.state = STATE_NONE;
+
+			/* memory barrier not required, we hold info->lock */
+			WRITE_ONCE(wait.state, STATE_NONE);
 			ret = wq_sleep(info, RECV, timeout, &wait);
 			msg_ptr = wait.msg;
 		}
diff --git a/ipc/msg.c b/ipc/msg.c
index 8dec945fa030..22ed09ded601 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -61,6 +61,16 @@ struct msg_queue {
 	struct list_head q_senders;
 } __randomize_layout;
 
+/*
+ * MSG_BARRIER Locking:
+ *
+ * Similar to the optimization used in ipc/mqueue.c, one syscall return path
+ * does not acquire any locks when it sees that a message exists in
+ * msg_receiver.r_msg. Therefore r_msg is set using smp_store_release()
+ * and accessed using READ_ONCE()+smp_acquire__after_ctrl_dep(). In addition,
+ * wake_q_add_safe() is used. See ipc/mqueue.c for more details
+ */
+
 /* one msg_receiver structure for each sleeping receiver */
 struct msg_receiver {
 	struct list_head	r_list;
@@ -184,6 +194,10 @@ static inline void ss_add(struct msg_queue *msq,
 {
 	mss->tsk = current;
 	mss->msgsz = msgsz;
+	/*
+	 * No memory barrier required: we did ipc_lock_object(),
+	 * and the waker obtains that lock before calling wake_q_add().
+	 */
 	__set_current_state(TASK_INTERRUPTIBLE);
 	list_add_tail(&mss->list, &msq->q_senders);
 }
@@ -237,8 +251,11 @@ static void expunge_all(struct msg_queue *msq, int res,
 	struct msg_receiver *msr, *t;
 
 	list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) {
-		wake_q_add(wake_q, msr->r_tsk);
-		WRITE_ONCE(msr->r_msg, ERR_PTR(res));
+		get_task_struct(msr->r_tsk);
+
+		/* see MSG_BARRIER for purpose/pairing */
+		smp_store_release(&msr->r_msg, ERR_PTR(res));
+		wake_q_add_safe(wake_q, msr->r_tsk);
 	}
 }
 
@@ -377,7 +394,7 @@ copy_msqid_from_user(struct msqid64_ds *out, void __user *buf, int version)
  * NOTE: no locks must be held, the rwsem is taken inside this function.
  */
 static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
-			struct msqid64_ds *msqid64)
+			struct ipc64_perm *perm, int msg_qbytes)
 {
 	struct kern_ipc_perm *ipcp;
 	struct msg_queue *msq;
@@ -387,7 +404,7 @@ static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
 	rcu_read_lock();
 
 	ipcp = ipcctl_obtain_check(ns, &msg_ids(ns), msqid, cmd,
-				      &msqid64->msg_perm, msqid64->msg_qbytes);
+				      perm, msg_qbytes);
 	if (IS_ERR(ipcp)) {
 		err = PTR_ERR(ipcp);
 		goto out_unlock1;
@@ -409,18 +426,18 @@ static int msgctl_down(struct ipc_namespace *ns, int msqid, int cmd,
 	{
 		DEFINE_WAKE_Q(wake_q);
 
-		if (msqid64->msg_qbytes > ns->msg_ctlmnb &&
+		if (msg_qbytes > ns->msg_ctlmnb &&
 		    !capable(CAP_SYS_RESOURCE)) {
 			err = -EPERM;
 			goto out_unlock1;
 		}
 
 		ipc_lock_object(&msq->q_perm);
-		err = ipc_update_perm(&msqid64->msg_perm, ipcp);
+		err = ipc_update_perm(perm, ipcp);
 		if (err)
 			goto out_unlock0;
 
-		msq->q_qbytes = msqid64->msg_qbytes;
+		msq->q_qbytes = msg_qbytes;
 
 		msq->q_ctime = ktime_get_real_seconds();
 		/*
@@ -601,9 +618,9 @@ static long ksys_msgctl(int msqid, int cmd, struct msqid_ds __user *buf, int ver
 	case IPC_SET:
 		if (copy_msqid_from_user(&msqid64, buf, version))
 			return -EFAULT;
-		/* fallthru */
+		 return msgctl_down(ns, msqid, cmd, &msqid64.msg_perm, msqid64.msg_qbytes);
 	case IPC_RMID:
-		return msgctl_down(ns, msqid, cmd, &msqid64);
+		return msgctl_down(ns, msqid, cmd, NULL, 0);
 	default:
 		return  -EINVAL;
 	}
@@ -735,9 +752,9 @@ static long compat_ksys_msgctl(int msqid, int cmd, void __user *uptr, int versio
 	case IPC_SET:
 		if (copy_compat_msqid_from_user(&msqid64, uptr, version))
 			return -EFAULT;
-		/* fallthru */
+		return msgctl_down(ns, msqid, cmd, &msqid64.msg_perm, msqid64.msg_qbytes);
 	case IPC_RMID:
-		return msgctl_down(ns, msqid, cmd, &msqid64);
+		return msgctl_down(ns, msqid, cmd, NULL, 0);
 	default:
 		return -EINVAL;
 	}
@@ -798,13 +815,17 @@ static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg,
 			list_del(&msr->r_list);
 			if (msr->r_maxsize < msg->m_ts) {
 				wake_q_add(wake_q, msr->r_tsk);
-				WRITE_ONCE(msr->r_msg, ERR_PTR(-E2BIG));
+
+				/* See expunge_all regarding memory barrier */
+				smp_store_release(&msr->r_msg, ERR_PTR(-E2BIG));
 			} else {
 				ipc_update_pid(&msq->q_lrpid, task_pid(msr->r_tsk));
 				msq->q_rtime = ktime_get_real_seconds();
 
 				wake_q_add(wake_q, msr->r_tsk);
-				WRITE_ONCE(msr->r_msg, msg);
+
+				/* See expunge_all regarding memory barrier */
+				smp_store_release(&msr->r_msg, msg);
 				return 1;
 			}
 		}
@@ -1154,7 +1175,11 @@ static long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, in
 			msr_d.r_maxsize = INT_MAX;
 		else
 			msr_d.r_maxsize = bufsz;
-		msr_d.r_msg = ERR_PTR(-EAGAIN);
+
+		/* memory barrier not require due to ipc_lock_object() */
+		WRITE_ONCE(msr_d.r_msg, ERR_PTR(-EAGAIN));
+
+		/* memory barrier not required, we own ipc_lock_object() */
 		__set_current_state(TASK_INTERRUPTIBLE);
 
 		ipc_unlock_object(&msq->q_perm);
@@ -1183,8 +1208,12 @@ static long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, in
 		 * signal) it will either see the message and continue ...
 		 */
 		msg = READ_ONCE(msr_d.r_msg);
-		if (msg != ERR_PTR(-EAGAIN))
+		if (msg != ERR_PTR(-EAGAIN)) {
+			/* see MSG_BARRIER for purpose/pairing */
+			smp_acquire__after_ctrl_dep();
+
 			goto out_unlock1;
+		}
 
 		 /*
 		  * ... or see -EAGAIN, acquire the lock to check the message
@@ -1192,7 +1221,7 @@ static long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, in
 		  */
 		ipc_lock_object(&msq->q_perm);
 
-		msg = msr_d.r_msg;
+		msg = READ_ONCE(msr_d.r_msg);
 		if (msg != ERR_PTR(-EAGAIN))
 			goto out_unlock0;
 
diff --git a/ipc/sem.c b/ipc/sem.c
index ec97a7072413..4f4303f32077 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -205,15 +205,38 @@ static int sysvipc_sem_proc_show(struct seq_file *s, void *it);
  *
  * Memory ordering:
  * Most ordering is enforced by using spin_lock() and spin_unlock().
- * The special case is use_global_lock:
+ *
+ * Exceptions:
+ * 1) use_global_lock: (SEM_BARRIER_1)
  * Setting it from non-zero to 0 is a RELEASE, this is ensured by
- * using smp_store_release().
+ * using smp_store_release(): Immediately after setting it to 0,
+ * a simple op can start.
  * Testing if it is non-zero is an ACQUIRE, this is ensured by using
  * smp_load_acquire().
  * Setting it from 0 to non-zero must be ordered with regards to
  * this smp_load_acquire(), this is guaranteed because the smp_load_acquire()
  * is inside a spin_lock() and after a write from 0 to non-zero a
  * spin_lock()+spin_unlock() is done.
+ *
+ * 2) queue.status: (SEM_BARRIER_2)
+ * Initialization is done while holding sem_lock(), so no further barrier is
+ * required.
+ * Setting it to a result code is a RELEASE, this is ensured by both a
+ * smp_store_release() (for case a) and while holding sem_lock()
+ * (for case b).
+ * The AQUIRE when reading the result code without holding sem_lock() is
+ * achieved by using READ_ONCE() + smp_acquire__after_ctrl_dep().
+ * (case a above).
+ * Reading the result code while holding sem_lock() needs no further barriers,
+ * the locks inside sem_lock() enforce ordering (case b above)
+ *
+ * 3) current->state:
+ * current->state is set to TASK_INTERRUPTIBLE while holding sem_lock().
+ * The wakeup is handled using the wake_q infrastructure. wake_q wakeups may
+ * happen immediately after calling wake_q_add. As wake_q_add_safe() is called
+ * when holding sem_lock(), no further barriers are required.
+ *
+ * See also ipc/mqueue.c for more details on the covered races.
  */
 
 #define sc_semmsl	sem_ctls[0]
@@ -344,12 +367,8 @@ static void complexmode_tryleave(struct sem_array *sma)
 		return;
 	}
 	if (sma->use_global_lock == 1) {
-		/*
-		 * Immediately after setting use_global_lock to 0,
-		 * a simple op can start. Thus: all memory writes
-		 * performed by the current operation must be visible
-		 * before we set use_global_lock to 0.
-		 */
+
+		/* See SEM_BARRIER_1 for purpose/pairing */
 		smp_store_release(&sma->use_global_lock, 0);
 	} else {
 		sma->use_global_lock--;
@@ -400,7 +419,7 @@ static inline int sem_lock(struct sem_array *sma, struct sembuf *sops,
 		 */
 		spin_lock(&sem->lock);
 
-		/* pairs with smp_store_release() */
+		/* see SEM_BARRIER_1 for purpose/pairing */
 		if (!smp_load_acquire(&sma->use_global_lock)) {
 			/* fast path successful! */
 			return sops->sem_num;
@@ -766,15 +785,12 @@ would_block:
 static inline void wake_up_sem_queue_prepare(struct sem_queue *q, int error,
 					     struct wake_q_head *wake_q)
 {
-	wake_q_add(wake_q, q->sleeper);
-	/*
-	 * Rely on the above implicit barrier, such that we can
-	 * ensure that we hold reference to the task before setting
-	 * q->status. Otherwise we could race with do_exit if the
-	 * task is awoken by an external event before calling
-	 * wake_up_process().
-	 */
-	WRITE_ONCE(q->status, error);
+	get_task_struct(q->sleeper);
+
+	/* see SEM_BARRIER_2 for purpuse/pairing */
+	smp_store_release(&q->status, error);
+
+	wake_q_add_safe(wake_q, q->sleeper);
 }
 
 static void unlink_queue(struct sem_array *sma, struct sem_queue *q)
@@ -2148,9 +2164,11 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops,
 	}
 
 	do {
+		/* memory ordering ensured by the lock in sem_lock() */
 		WRITE_ONCE(queue.status, -EINTR);
 		queue.sleeper = current;
 
+		/* memory ordering is ensured by the lock in sem_lock() */
 		__set_current_state(TASK_INTERRUPTIBLE);
 		sem_unlock(sma, locknum);
 		rcu_read_unlock();
@@ -2173,13 +2191,8 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops,
 		 */
 		error = READ_ONCE(queue.status);
 		if (error != -EINTR) {
-			/*
-			 * User space could assume that semop() is a memory
-			 * barrier: Without the mb(), the cpu could
-			 * speculatively read in userspace stale data that was
-			 * overwritten by the previous owner of the semaphore.
-			 */
-			smp_mb();
+			/* see SEM_BARRIER_2 for purpose/pairing */
+			smp_acquire__after_ctrl_dep();
 			goto out_free;
 		}
 
@@ -2189,6 +2202,9 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops,
 		if (!ipc_valid_object(&sma->sem_perm))
 			goto out_unlock_free;
 
+		/*
+		 * No necessity for any barrier: We are protect by sem_lock()
+		 */
 		error = READ_ONCE(queue.status);
 
 		/*
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index c74761004ee5..ece7e13f6e4a 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1457,7 +1457,7 @@ static int xol_add_vma(struct mm_struct *mm, struct xol_area *area)
 		/* Try to map as high as possible, this is only a hint. */
 		area->vaddr = get_unmapped_area(NULL, TASK_SIZE - PAGE_SIZE,
 						PAGE_SIZE, 0, 0);
-		if (area->vaddr & ~PAGE_MASK) {
+		if (IS_ERR_VALUE(area->vaddr)) {
 			ret = area->vaddr;
 			goto fail;
 		}
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index 14a625c16cb3..f1443abb31f1 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -49,6 +49,7 @@ unsigned long __read_mostly sysctl_hung_task_timeout_secs = CONFIG_DEFAULT_HUNG_
 unsigned long __read_mostly sysctl_hung_task_check_interval_secs;
 
 int __read_mostly sysctl_hung_task_warnings = 10;
+int __read_mostly sysctl_hung_task_interval_warnings;
 
 static int __read_mostly did_panic;
 static bool hung_task_show_lock;
@@ -85,6 +86,34 @@ static struct notifier_block panic_block = {
 	.notifier_call = hung_task_panic,
 };
 
+static void hung_task_warning(struct task_struct *t, bool timeout)
+{
+	const char *loglevel = timeout ? KERN_ERR : KERN_INFO;
+	const char *path;
+	int *warnings;
+
+	if (timeout) {
+		warnings = &sysctl_hung_task_warnings;
+		path = "hung_task_timeout_secs";
+	} else {
+		warnings = &sysctl_hung_task_interval_warnings;
+		path = "hung_task_interval_secs";
+	}
+
+	if (*warnings > 0)
+		--*warnings;
+
+	printk("%sINFO: task %s:%d blocked for more than %ld seconds.\n",
+	       loglevel, t->comm, t->pid, (jiffies - t->last_switch_time) / HZ);
+	printk("%s      %s %s %.*s\n",
+		loglevel, print_tainted(), init_utsname()->release,
+		(int)strcspn(init_utsname()->version, " "),
+		init_utsname()->version);
+	printk("%s\"echo 0 > /proc/sys/kernel/%s\" disables this message.\n",
+		loglevel, path);
+	sched_show_task(t);
+}
+
 static void check_hung_task(struct task_struct *t, unsigned long timeout)
 {
 	unsigned long switch_count = t->nvcsw + t->nivcsw;
@@ -109,6 +138,9 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
 		t->last_switch_time = jiffies;
 		return;
 	}
+	if (sysctl_hung_task_interval_warnings)
+		hung_task_warning(t, false);
+
 	if (time_is_after_jiffies(t->last_switch_time + timeout * HZ))
 		return;
 
@@ -120,28 +152,57 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
 		hung_task_call_panic = true;
 	}
 
-	/*
-	 * Ok, the task did not get scheduled for more than 2 minutes,
-	 * complain:
-	 */
 	if (sysctl_hung_task_warnings) {
-		if (sysctl_hung_task_warnings > 0)
-			sysctl_hung_task_warnings--;
-		pr_err("INFO: task %s:%d blocked for more than %ld seconds.\n",
-		       t->comm, t->pid, (jiffies - t->last_switch_time) / HZ);
-		pr_err("      %s %s %.*s\n",
-			print_tainted(), init_utsname()->release,
-			(int)strcspn(init_utsname()->version, " "),
-			init_utsname()->version);
-		pr_err("\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\""
-			" disables this message.\n");
-		sched_show_task(t);
+		/* Don't print warings twice */
+		if (!sysctl_hung_task_interval_warnings)
+			hung_task_warning(t, true);
 		hung_task_show_lock = true;
 	}
 
 	touch_nmi_watchdog();
 }
 
+static void check_killed_task(struct task_struct *t, unsigned long timeout)
+{
+	unsigned long stamp = t->killed_time;
+
+	/*
+	 * Ensure the task is not frozen.
+	 * Also, skip vfork and any other user process that freezer should skip.
+	 */
+	if (unlikely(t->flags & (PF_FROZEN | PF_FREEZER_SKIP)))
+		return;
+	/*
+	 * Skip threads which are already inside do_exit(), for exit_mm() etc.
+	 * might take many seconds.
+	 */
+	if (t->flags & PF_EXITING)
+		return;
+	if (!stamp) {
+		stamp = jiffies;
+		if (!stamp)
+			stamp++;
+		t->killed_time = stamp;
+		return;
+	}
+	if (time_is_after_jiffies(stamp + timeout * HZ))
+		return;
+	trace_sched_process_hang(t);
+	if (sysctl_hung_task_panic) {
+		console_verbose();
+		hung_task_call_panic = true;
+	}
+	/*
+	 * This thread failed to terminate for more than
+	 * sysctl_hung_task_timeout_secs seconds, complain:
+	 */
+	pr_err("INFO: task %s:%d can't die for more than %ld seconds.\n",
+	       t->comm, t->pid, (jiffies - stamp) / HZ);
+	sched_show_task(t);
+	hung_task_show_lock = true;
+	touch_nmi_watchdog();
+}
+
 /*
  * To avoid extending the RCU grace period for an unbounded amount of time,
  * periodically exit the critical section and enter a new one.
@@ -193,6 +254,9 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout)
 				goto unlock;
 			last_break = jiffies;
 		}
+		/* Check threads which are about to terminate. */
+		if (unlikely(fatal_signal_pending(t)))
+			check_killed_task(t, timeout);
 		/* use "==" to skip the TASK_KILLABLE tasks waiting on NFS */
 		if (t->state == TASK_UNINTERRUPTIBLE)
 			check_hung_task(t, timeout);
diff --git a/kernel/notifier.c b/kernel/notifier.c
index d9f5081d578d..63d7501ac638 100644
--- a/kernel/notifier.c
+++ b/kernel/notifier.c
@@ -23,22 +23,10 @@ static int notifier_chain_register(struct notifier_block **nl,
 		struct notifier_block *n)
 {
 	while ((*nl) != NULL) {
-		WARN_ONCE(((*nl) == n), "double register detected");
-		if (n->priority > (*nl)->priority)
-			break;
-		nl = &((*nl)->next);
-	}
-	n->next = *nl;
-	rcu_assign_pointer(*nl, n);
-	return 0;
-}
-
-static int notifier_chain_cond_register(struct notifier_block **nl,
-		struct notifier_block *n)
-{
-	while ((*nl) != NULL) {
-		if ((*nl) == n)
+		if (unlikely((*nl) == n)) {
+			WARN(1, "double register detected");
 			return 0;
+		}
 		if (n->priority > (*nl)->priority)
 			break;
 		nl = &((*nl)->next);
@@ -233,29 +221,6 @@ int blocking_notifier_chain_register(struct blocking_notifier_head *nh,
 EXPORT_SYMBOL_GPL(blocking_notifier_chain_register);
 
 /**
- *	blocking_notifier_chain_cond_register - Cond add notifier to a blocking notifier chain
- *	@nh: Pointer to head of the blocking notifier chain
- *	@n: New entry in notifier chain
- *
- *	Adds a notifier to a blocking notifier chain, only if not already
- *	present in the chain.
- *	Must be called in process context.
- *
- *	Currently always returns zero.
- */
-int blocking_notifier_chain_cond_register(struct blocking_notifier_head *nh,
-		struct notifier_block *n)
-{
-	int ret;
-
-	down_write(&nh->rwsem);
-	ret = notifier_chain_cond_register(&nh->head, n);
-	up_write(&nh->rwsem);
-	return ret;
-}
-EXPORT_SYMBOL_GPL(blocking_notifier_chain_cond_register);
-
-/**
  *	blocking_notifier_chain_unregister - Remove notifier from a blocking notifier chain
  *	@nh: Pointer to head of the blocking notifier chain
  *	@n: Entry to remove from notifier chain
diff --git a/kernel/profile.c b/kernel/profile.c
index af7c94bf5fa1..4b144b02ca5d 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -336,7 +336,7 @@ static int profile_dead_cpu(unsigned int cpu)
 	struct page *page;
 	int i;
 
-	if (prof_cpu_mask != NULL)
+	if (cpumask_available(prof_cpu_mask))
 		cpumask_clear_cpu(cpu, prof_cpu_mask);
 
 	for (i = 0; i < 2; i++) {
@@ -373,7 +373,7 @@ static int profile_prepare_cpu(unsigned int cpu)
 
 static int profile_online_cpu(unsigned int cpu)
 {
-	if (prof_cpu_mask != NULL)
+	if (cpumask_available(prof_cpu_mask))
 		cpumask_set_cpu(cpu, prof_cpu_mask);
 
 	return 0;
@@ -403,7 +403,7 @@ void profile_tick(int type)
 {
 	struct pt_regs *regs = get_irq_regs();
 
-	if (!user_mode(regs) && prof_cpu_mask != NULL &&
+	if (!user_mode(regs) && cpumask_available(prof_cpu_mask) &&
 	    cpumask_test_cpu(smp_processor_id(), prof_cpu_mask))
 		profile_hit(type, (void *)profile_pc(regs));
 }
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index b6f2f35d0bcf..31ece1120aa4 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1148,6 +1148,14 @@ static struct ctl_table kern_table[] = {
 		.proc_handler	= proc_dointvec_minmax,
 		.extra1		= &neg_one,
 	},
+	{
+		.procname	= "hung_task_interval_warnings",
+		.data		= &sysctl_hung_task_interval_warnings,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &neg_one,
+	},
 #endif
 #ifdef CONFIG_RT_MUTEXES
 	{
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 27ff08ce03e9..83a804d58e2f 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2147,6 +2147,12 @@ config IO_STRICT_DEVMEM
 
 	  If in doubt, say Y.
 
+config DEBUG_AID_FOR_SYZBOT
+       bool "Additional debug code for syzbot"
+       default n
+       help
+         This option is intended for testing by syzbot.
+
 source "arch/$(SRCARCH)/Kconfig.debug"
 
 endmenu # Kernel hacking
diff --git a/lib/math/rational.c b/lib/math/rational.c
index ba7443677c90..31fb27db2deb 100644
--- a/lib/math/rational.c
+++ b/lib/math/rational.c
@@ -3,6 +3,7 @@
  * rational fractions
  *
  * Copyright (C) 2009 emlix GmbH, Oskar Schirmer <oskar@scara.com>
+ * Copyright (C) 2019 Trent Piepho <tpiepho@gmail.com>
  *
  * helper functions when coping with rational numbers
  */
@@ -10,6 +11,7 @@
 #include <linux/rational.h>
 #include <linux/compiler.h>
 #include <linux/export.h>
+#include <linux/kernel.h>
 
 /*
  * calculate best rational approximation for a given fraction
@@ -33,30 +35,65 @@ void rational_best_approximation(
 	unsigned long max_numerator, unsigned long max_denominator,
 	unsigned long *best_numerator, unsigned long *best_denominator)
 {
-	unsigned long n, d, n0, d0, n1, d1;
+	/* n/d is the starting rational, which is continually
+	 * decreased each iteration using the Euclidean algorithm.
+	 *
+	 * dp is the value of d from the prior iteration.
+	 *
+	 * n2/d2, n1/d1, and n0/d0 are our successively more accurate
+	 * approximations of the rational.  They are, respectively,
+	 * the current, previous, and two prior iterations of it.
+	 *
+	 * a is current term of the continued fraction.
+	 */
+	unsigned long n, d, n0, d0, n1, d1, n2, d2;
 	n = given_numerator;
 	d = given_denominator;
 	n0 = d1 = 0;
 	n1 = d0 = 1;
+
 	for (;;) {
-		unsigned long t, a;
-		if ((n1 > max_numerator) || (d1 > max_denominator)) {
-			n1 = n0;
-			d1 = d0;
-			break;
-		}
+		unsigned long dp, a;
+
 		if (d == 0)
 			break;
-		t = d;
+		/* Find next term in continued fraction, 'a', via
+		 * Euclidean algorithm.
+		 */
+		dp = d;
 		a = n / d;
 		d = n % d;
-		n = t;
-		t = n0 + a * n1;
+		n = dp;
+
+		/* Calculate the current rational approximation (aka
+		 * convergent), n2/d2, using the term just found and
+		 * the two prior approximations.
+		 */
+		n2 = n0 + a * n1;
+		d2 = d0 + a * d1;
+
+		/* If the current convergent exceeds the maxes, then
+		 * return either the previous convergent or the
+		 * largest semi-convergent, the final term of which is
+		 * found below as 't'.
+		 */
+		if ((n2 > max_numerator) || (d2 > max_denominator)) {
+			unsigned long t = min((max_numerator - n0) / n1,
+					      (max_denominator - d0) / d1);
+
+			/* This tests if the semi-convergent is closer
+			 * than the previous convergent.
+			 */
+			if (2u * t > a || (2u * t == a && d0 * dp > d1 * d)) {
+				n1 = n0 + t * n1;
+				d1 = d0 + t * d1;
+			}
+			break;
+		}
 		n0 = n1;
-		n1 = t;
-		t = d0 + a * d1;
+		n1 = n2;
 		d0 = d1;
-		d1 = t;
+		d1 = d2;
 	}
 	*best_numerator = n1;
 	*best_denominator = d1;
diff --git a/lib/ubsan.c b/lib/ubsan.c
index 0c4681118fcd..f007a406f89c 100644
--- a/lib/ubsan.c
+++ b/lib/ubsan.c
@@ -140,25 +140,21 @@ static void val_to_string(char *str, size_t size, struct type_descriptor *type,
 	}
 }
 
-static DEFINE_SPINLOCK(report_lock);
-
-static void ubsan_prologue(struct source_location *location,
-			unsigned long *flags)
+static void ubsan_prologue(struct source_location *location)
 {
 	current->in_ubsan++;
-	spin_lock_irqsave(&report_lock, *flags);
 
 	pr_err("========================================"
 		"========================================\n");
 	print_source_location("UBSAN: Undefined behaviour in", location);
 }
 
-static void ubsan_epilogue(unsigned long *flags)
+static void ubsan_epilogue(void)
 {
 	dump_stack();
 	pr_err("========================================"
 		"========================================\n");
-	spin_unlock_irqrestore(&report_lock, *flags);
+
 	current->in_ubsan--;
 }
 
@@ -167,14 +163,13 @@ static void handle_overflow(struct overflow_data *data, void *lhs,
 {
 
 	struct type_descriptor *type = data->type;
-	unsigned long flags;
 	char lhs_val_str[VALUE_LENGTH];
 	char rhs_val_str[VALUE_LENGTH];
 
 	if (suppress_report(&data->location))
 		return;
 
-	ubsan_prologue(&data->location, &flags);
+	ubsan_prologue(&data->location);
 
 	val_to_string(lhs_val_str, sizeof(lhs_val_str), type, lhs);
 	val_to_string(rhs_val_str, sizeof(rhs_val_str), type, rhs);
@@ -186,7 +181,7 @@ static void handle_overflow(struct overflow_data *data, void *lhs,
 		rhs_val_str,
 		type->type_name);
 
-	ubsan_epilogue(&flags);
+	ubsan_epilogue();
 }
 
 void __ubsan_handle_add_overflow(struct overflow_data *data,
@@ -214,20 +209,19 @@ EXPORT_SYMBOL(__ubsan_handle_mul_overflow);
 void __ubsan_handle_negate_overflow(struct overflow_data *data,
 				void *old_val)
 {
-	unsigned long flags;
 	char old_val_str[VALUE_LENGTH];
 
 	if (suppress_report(&data->location))
 		return;
 
-	ubsan_prologue(&data->location, &flags);
+	ubsan_prologue(&data->location);
 
 	val_to_string(old_val_str, sizeof(old_val_str), data->type, old_val);
 
 	pr_err("negation of %s cannot be represented in type %s:\n",
 		old_val_str, data->type->type_name);
 
-	ubsan_epilogue(&flags);
+	ubsan_epilogue();
 }
 EXPORT_SYMBOL(__ubsan_handle_negate_overflow);
 
@@ -235,13 +229,12 @@ EXPORT_SYMBOL(__ubsan_handle_negate_overflow);
 void __ubsan_handle_divrem_overflow(struct overflow_data *data,
 				void *lhs, void *rhs)
 {
-	unsigned long flags;
 	char rhs_val_str[VALUE_LENGTH];
 
 	if (suppress_report(&data->location))
 		return;
 
-	ubsan_prologue(&data->location, &flags);
+	ubsan_prologue(&data->location);
 
 	val_to_string(rhs_val_str, sizeof(rhs_val_str), data->type, rhs);
 
@@ -251,58 +244,52 @@ void __ubsan_handle_divrem_overflow(struct overflow_data *data,
 	else
 		pr_err("division by zero\n");
 
-	ubsan_epilogue(&flags);
+	ubsan_epilogue();
 }
 EXPORT_SYMBOL(__ubsan_handle_divrem_overflow);
 
 static void handle_null_ptr_deref(struct type_mismatch_data_common *data)
 {
-	unsigned long flags;
-
 	if (suppress_report(data->location))
 		return;
 
-	ubsan_prologue(data->location, &flags);
+	ubsan_prologue(data->location);
 
 	pr_err("%s null pointer of type %s\n",
 		type_check_kinds[data->type_check_kind],
 		data->type->type_name);
 
-	ubsan_epilogue(&flags);
+	ubsan_epilogue();
 }
 
 static void handle_misaligned_access(struct type_mismatch_data_common *data,
 				unsigned long ptr)
 {
-	unsigned long flags;
-
 	if (suppress_report(data->location))
 		return;
 
-	ubsan_prologue(data->location, &flags);
+	ubsan_prologue(data->location);
 
 	pr_err("%s misaligned address %p for type %s\n",
 		type_check_kinds[data->type_check_kind],
 		(void *)ptr, data->type->type_name);
 	pr_err("which requires %ld byte alignment\n", data->alignment);
 
-	ubsan_epilogue(&flags);
+	ubsan_epilogue();
 }
 
 static void handle_object_size_mismatch(struct type_mismatch_data_common *data,
 					unsigned long ptr)
 {
-	unsigned long flags;
-
 	if (suppress_report(data->location))
 		return;
 
-	ubsan_prologue(data->location, &flags);
+	ubsan_prologue(data->location);
 	pr_err("%s address %p with insufficient space\n",
 		type_check_kinds[data->type_check_kind],
 		(void *) ptr);
 	pr_err("for an object of type %s\n", data->type->type_name);
-	ubsan_epilogue(&flags);
+	ubsan_epilogue();
 }
 
 static void ubsan_type_mismatch_common(struct type_mismatch_data_common *data,
@@ -351,25 +338,23 @@ EXPORT_SYMBOL(__ubsan_handle_type_mismatch_v1);
 
 void __ubsan_handle_out_of_bounds(struct out_of_bounds_data *data, void *index)
 {
-	unsigned long flags;
 	char index_str[VALUE_LENGTH];
 
 	if (suppress_report(&data->location))
 		return;
 
-	ubsan_prologue(&data->location, &flags);
+	ubsan_prologue(&data->location);
 
 	val_to_string(index_str, sizeof(index_str), data->index_type, index);
 	pr_err("index %s is out of range for type %s\n", index_str,
 		data->array_type->type_name);
-	ubsan_epilogue(&flags);
+	ubsan_epilogue();
 }
 EXPORT_SYMBOL(__ubsan_handle_out_of_bounds);
 
 void __ubsan_handle_shift_out_of_bounds(struct shift_out_of_bounds_data *data,
 					void *lhs, void *rhs)
 {
-	unsigned long flags;
 	struct type_descriptor *rhs_type = data->rhs_type;
 	struct type_descriptor *lhs_type = data->lhs_type;
 	char rhs_str[VALUE_LENGTH];
@@ -379,7 +364,7 @@ void __ubsan_handle_shift_out_of_bounds(struct shift_out_of_bounds_data *data,
 	if (suppress_report(&data->location))
 		goto out;
 
-	ubsan_prologue(&data->location, &flags);
+	ubsan_prologue(&data->location);
 
 	val_to_string(rhs_str, sizeof(rhs_str), rhs_type, rhs);
 	val_to_string(lhs_str, sizeof(lhs_str), lhs_type, lhs);
@@ -402,7 +387,7 @@ void __ubsan_handle_shift_out_of_bounds(struct shift_out_of_bounds_data *data,
 			lhs_str, rhs_str,
 			lhs_type->type_name);
 
-	ubsan_epilogue(&flags);
+	ubsan_epilogue();
 out:
 	user_access_restore(ua_flags);
 }
@@ -411,11 +396,9 @@ EXPORT_SYMBOL(__ubsan_handle_shift_out_of_bounds);
 
 void __ubsan_handle_builtin_unreachable(struct unreachable_data *data)
 {
-	unsigned long flags;
-
-	ubsan_prologue(&data->location, &flags);
+	ubsan_prologue(&data->location);
 	pr_err("calling __builtin_unreachable()\n");
-	ubsan_epilogue(&flags);
+	ubsan_epilogue();
 	panic("can't return from __builtin_unreachable()");
 }
 EXPORT_SYMBOL(__ubsan_handle_builtin_unreachable);
@@ -423,19 +406,18 @@ EXPORT_SYMBOL(__ubsan_handle_builtin_unreachable);
 void __ubsan_handle_load_invalid_value(struct invalid_value_data *data,
 				void *val)
 {
-	unsigned long flags;
 	char val_str[VALUE_LENGTH];
 
 	if (suppress_report(&data->location))
 		return;
 
-	ubsan_prologue(&data->location, &flags);
+	ubsan_prologue(&data->location);
 
 	val_to_string(val_str, sizeof(val_str), data->type, val);
 
 	pr_err("load of value %s is not a valid value for type %s\n",
 		val_str, data->type->type_name);
 
-	ubsan_epilogue(&flags);
+	ubsan_epilogue();
 }
 EXPORT_SYMBOL(__ubsan_handle_load_invalid_value);
diff --git a/mm/cma.c b/mm/cma.c
index 7fe0b8356775..be55d1988c67 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -95,13 +95,11 @@ static void cma_clear_bitmap(struct cma *cma, unsigned long pfn,
 
 static int __init cma_activate_area(struct cma *cma)
 {
-	int bitmap_size = BITS_TO_LONGS(cma_bitmap_maxno(cma)) * sizeof(long);
 	unsigned long base_pfn = cma->base_pfn, pfn = base_pfn;
 	unsigned i = cma->count >> pageblock_order;
 	struct zone *zone;
 
-	cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
-
+	cma->bitmap = bitmap_zalloc(cma_bitmap_maxno(cma), GFP_KERNEL);
 	if (!cma->bitmap) {
 		cma->count = 0;
 		return -ENOMEM;
@@ -139,7 +137,7 @@ static int __init cma_activate_area(struct cma *cma)
 
 not_in_zone:
 	pr_err("CMA area %s could not be activated\n", cma->name);
-	kfree(cma->bitmap);
+	bitmap_free(cma->bitmap);
 	cma->count = 0;
 	return -EINVAL;
 }
diff --git a/mm/filemap.c b/mm/filemap.c
index 85b7d087eb45..1f5731768222 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2329,27 +2329,6 @@ EXPORT_SYMBOL(generic_file_read_iter);
 
 #ifdef CONFIG_MMU
 #define MMAP_LOTSAMISS  (100)
-static struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf,
-					     struct file *fpin)
-{
-	int flags = vmf->flags;
-
-	if (fpin)
-		return fpin;
-
-	/*
-	 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or
-	 * anything, so we only pin the file and drop the mmap_sem if only
-	 * FAULT_FLAG_ALLOW_RETRY is set.
-	 */
-	if ((flags & (FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_RETRY_NOWAIT)) ==
-	    FAULT_FLAG_ALLOW_RETRY) {
-		fpin = get_file(vmf->vma->vm_file);
-		up_read(&vmf->vma->vm_mm->mmap_sem);
-	}
-	return fpin;
-}
-
 /*
  * lock_page_maybe_drop_mmap - lock the page, possibly dropping the mmap_sem
  * @vmf - the vm_fault for this fault.
diff --git a/mm/gup.c b/mm/gup.c
index 8f236a335ae9..c2b3e117d706 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1443,6 +1443,7 @@ static long check_and_migrate_cma_pages(struct task_struct *tsk,
 	bool drain_allow = true;
 	bool migrate_allow = true;
 	LIST_HEAD(cma_page_list);
+	long ret = nr_pages;
 
 check_again:
 	for (i = 0; i < nr_pages;) {
@@ -1504,17 +1505,18 @@ check_again:
 		 * again migrating any new CMA pages which we failed to isolate
 		 * earlier.
 		 */
-		nr_pages = __get_user_pages_locked(tsk, mm, start, nr_pages,
+		ret = __get_user_pages_locked(tsk, mm, start, nr_pages,
 						   pages, vmas, NULL,
 						   gup_flags);
 
-		if ((nr_pages > 0) && migrate_allow) {
+		if ((ret > 0) && migrate_allow) {
+			nr_pages = ret;
 			drain_allow = true;
 			goto check_again;
 		}
 	}
 
-	return nr_pages;
+	return ret;
 }
 #else
 static long check_and_migrate_cma_pages(struct task_struct *tsk,
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 13cc93785006..b68c13e564d1 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -686,20 +686,18 @@ static inline gfp_t alloc_hugepage_direct_gfpmask(struct vm_area_struct *vma)
 }
 
 /* Caller must hold page table lock. */
-static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
+static void set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
 		struct vm_area_struct *vma, unsigned long haddr, pmd_t *pmd,
 		struct page *zero_page)
 {
 	pmd_t entry;
-	if (!pmd_none(*pmd))
-		return false;
+
 	entry = mk_pmd(zero_page, vma->vm_page_prot);
 	entry = pmd_mkhuge(entry);
 	if (pgtable)
 		pgtable_trans_huge_deposit(mm, pmd, pgtable);
 	set_pmd_at(mm, haddr, pmd, entry);
 	mm_inc_nr_ptes(mm);
-	return true;
 }
 
 vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index b45a95363a84..a5c2c880af27 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -244,16 +244,66 @@ struct file_region {
 	long to;
 };
 
+/* Must be called with resv->lock held. Calling this with count_only == true
+ * will count the number of pages to be added but will not modify the linked
+ * list.
+ */
+static long add_reservation_in_range(struct resv_map *resv, long f, long t,
+				     bool count_only)
+{
+	long chg = 0;
+	struct list_head *head = &resv->regions;
+	struct file_region *rg = NULL, *trg = NULL, *nrg = NULL;
+
+	/* Locate the region we are before or in. */
+	list_for_each_entry(rg, head, link)
+		if (f <= rg->to)
+			break;
+
+	/* Round our left edge to the current segment if it encloses us. */
+	if (f > rg->from)
+		f = rg->from;
+
+	chg = t - f;
+
+	/* Check for and consume any regions we now overlap with. */
+	nrg = rg;
+	list_for_each_entry_safe(rg, trg, rg->link.prev, link) {
+		if (&rg->link == head)
+			break;
+		if (rg->from > t)
+			break;
+
+		/* We overlap with this area, if it extends further than
+		 * us then we must extend ourselves.  Account for its
+		 * existing reservation.
+		 */
+		if (rg->to > t) {
+			chg += rg->to - t;
+			t = rg->to;
+		}
+		chg -= rg->to - rg->from;
+
+		if (!count_only && rg != nrg) {
+			list_del(&rg->link);
+			kfree(rg);
+		}
+	}
+
+	if (!count_only) {
+		nrg->from = f;
+		nrg->to = t;
+	}
+
+	return chg;
+}
+
 /*
  * Add the huge page range represented by [f, t) to the reserve
- * map.  In the normal case, existing regions will be expanded
- * to accommodate the specified range.  Sufficient regions should
- * exist for expansion due to the previous call to region_chg
- * with the same range.  However, it is possible that region_del
- * could have been called after region_chg and modifed the map
- * in such a way that no region exists to be expanded.  In this
- * case, pull a region descriptor from the cache associated with
- * the map and use that for the new range.
+ * map.  Existing regions will be expanded to accommodate the specified
+ * range, or a region will be taken from the cache.  Sufficient regions
+ * must exist in the cache due to the previous call to region_chg with
+ * the same range.
  *
  * Return the number of new huge pages added to the map.  This
  * number is greater than or equal to zero.
@@ -261,7 +311,7 @@ struct file_region {
 static long region_add(struct resv_map *resv, long f, long t)
 {
 	struct list_head *head = &resv->regions;
-	struct file_region *rg, *nrg, *trg;
+	struct file_region *rg, *nrg;
 	long add = 0;
 
 	spin_lock(&resv->lock);
@@ -272,9 +322,8 @@ static long region_add(struct resv_map *resv, long f, long t)
 
 	/*
 	 * If no region exists which can be expanded to include the
-	 * specified range, the list must have been modified by an
-	 * interleving call to region_del().  Pull a region descriptor
-	 * from the cache and use it for this range.
+	 * specified range, pull a region descriptor from the cache
+	 * and use it for this range.
 	 */
 	if (&rg->link == head || t < rg->from) {
 		VM_BUG_ON(resv->region_cache_count <= 0);
@@ -292,38 +341,7 @@ static long region_add(struct resv_map *resv, long f, long t)
 		goto out_locked;
 	}
 
-	/* Round our left edge to the current segment if it encloses us. */
-	if (f > rg->from)
-		f = rg->from;
-
-	/* Check for and consume any regions we now overlap with. */
-	nrg = rg;
-	list_for_each_entry_safe(rg, trg, rg->link.prev, link) {
-		if (&rg->link == head)
-			break;
-		if (rg->from > t)
-			break;
-
-		/* If this area reaches higher then extend our area to
-		 * include it completely.  If this is not the first area
-		 * which we intend to reuse, free it. */
-		if (rg->to > t)
-			t = rg->to;
-		if (rg != nrg) {
-			/* Decrement return value by the deleted range.
-			 * Another range will span this area so that by
-			 * end of routine add will be >= zero
-			 */
-			add -= (rg->to - rg->from);
-			list_del(&rg->link);
-			kfree(rg);
-		}
-	}
-
-	add += (nrg->from - f);		/* Added to beginning of region */
-	nrg->from = f;
-	add += t - nrg->to;		/* Added to end of region */
-	nrg->to = t;
+	add = add_reservation_in_range(resv, f, t, false);
 
 out_locked:
 	resv->adds_in_progress--;
@@ -339,15 +357,9 @@ out_locked:
  * call to region_add that will actually modify the reserve
  * map to add the specified range [f, t).  region_chg does
  * not change the number of huge pages represented by the
- * map.  However, if the existing regions in the map can not
- * be expanded to represent the new range, a new file_region
- * structure is added to the map as a placeholder.  This is
- * so that the subsequent region_add call will have all the
- * regions it needs and will not fail.
- *
- * Upon entry, region_chg will also examine the cache of region descriptors
- * associated with the map.  If there are not enough descriptors cached, one
- * will be allocated for the in progress add operation.
+ * map.  A new file_region structure is added to the cache
+ * as a placeholder, so that the subsequent region_add
+ * call will have all the regions it needs and will not fail.
  *
  * Returns the number of huge pages that need to be added to the existing
  * reservation map for the range [f, t).  This number is greater or equal to
@@ -356,11 +368,8 @@ out_locked:
  */
 static long region_chg(struct resv_map *resv, long f, long t)
 {
-	struct list_head *head = &resv->regions;
-	struct file_region *rg, *nrg = NULL;
 	long chg = 0;
 
-retry:
 	spin_lock(&resv->lock);
 retry_locked:
 	resv->adds_in_progress++;
@@ -378,10 +387,8 @@ retry_locked:
 		spin_unlock(&resv->lock);
 
 		trg = kmalloc(sizeof(*trg), GFP_KERNEL);
-		if (!trg) {
-			kfree(nrg);
+		if (!trg)
 			return -ENOMEM;
-		}
 
 		spin_lock(&resv->lock);
 		list_add(&trg->link, &resv->region_cache);
@@ -389,61 +396,8 @@ retry_locked:
 		goto retry_locked;
 	}
 
-	/* Locate the region we are before or in. */
-	list_for_each_entry(rg, head, link)
-		if (f <= rg->to)
-			break;
+	chg = add_reservation_in_range(resv, f, t, true);
 
-	/* If we are below the current region then a new region is required.
-	 * Subtle, allocate a new region at the position but make it zero
-	 * size such that we can guarantee to record the reservation. */
-	if (&rg->link == head || t < rg->from) {
-		if (!nrg) {
-			resv->adds_in_progress--;
-			spin_unlock(&resv->lock);
-			nrg = kmalloc(sizeof(*nrg), GFP_KERNEL);
-			if (!nrg)
-				return -ENOMEM;
-
-			nrg->from = f;
-			nrg->to   = f;
-			INIT_LIST_HEAD(&nrg->link);
-			goto retry;
-		}
-
-		list_add(&nrg->link, rg->link.prev);
-		chg = t - f;
-		goto out_nrg;
-	}
-
-	/* Round our left edge to the current segment if it encloses us. */
-	if (f > rg->from)
-		f = rg->from;
-	chg = t - f;
-
-	/* Check for and consume any regions we now overlap with. */
-	list_for_each_entry(rg, rg->link.prev, link) {
-		if (&rg->link == head)
-			break;
-		if (rg->from > t)
-			goto out;
-
-		/* We overlap with this area, if it extends further than
-		 * us then we must extend ourselves.  Account for its
-		 * existing reservation. */
-		if (rg->to > t) {
-			chg += rg->to - t;
-			t = rg->to;
-		}
-		chg -= rg->to - rg->from;
-	}
-
-out:
-	spin_unlock(&resv->lock);
-	/*  We already know we raced and no longer need the new region */
-	kfree(nrg);
-	return chg;
-out_nrg:
 	spin_unlock(&resv->lock);
 	return chg;
 }
@@ -1069,85 +1023,12 @@ static void free_gigantic_page(struct page *page, unsigned int order)
 }
 
 #ifdef CONFIG_CONTIG_ALLOC
-static int __alloc_gigantic_page(unsigned long start_pfn,
-				unsigned long nr_pages, gfp_t gfp_mask)
-{
-	unsigned long end_pfn = start_pfn + nr_pages;
-	return alloc_contig_range(start_pfn, end_pfn, MIGRATE_MOVABLE,
-				  gfp_mask);
-}
-
-static bool pfn_range_valid_gigantic(struct zone *z,
-			unsigned long start_pfn, unsigned long nr_pages)
-{
-	unsigned long i, end_pfn = start_pfn + nr_pages;
-	struct page *page;
-
-	for (i = start_pfn; i < end_pfn; i++) {
-		page = pfn_to_online_page(i);
-		if (!page)
-			return false;
-
-		if (page_zone(page) != z)
-			return false;
-
-		if (PageReserved(page))
-			return false;
-
-		if (page_count(page) > 0)
-			return false;
-
-		if (PageHuge(page))
-			return false;
-	}
-
-	return true;
-}
-
-static bool zone_spans_last_pfn(const struct zone *zone,
-			unsigned long start_pfn, unsigned long nr_pages)
-{
-	unsigned long last_pfn = start_pfn + nr_pages - 1;
-	return zone_spans_pfn(zone, last_pfn);
-}
-
 static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
 		int nid, nodemask_t *nodemask)
 {
-	unsigned int order = huge_page_order(h);
-	unsigned long nr_pages = 1 << order;
-	unsigned long ret, pfn, flags;
-	struct zonelist *zonelist;
-	struct zone *zone;
-	struct zoneref *z;
-
-	zonelist = node_zonelist(nid, gfp_mask);
-	for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(gfp_mask), nodemask) {
-		spin_lock_irqsave(&zone->lock, flags);
-
-		pfn = ALIGN(zone->zone_start_pfn, nr_pages);
-		while (zone_spans_last_pfn(zone, pfn, nr_pages)) {
-			if (pfn_range_valid_gigantic(zone, pfn, nr_pages)) {
-				/*
-				 * We release the zone lock here because
-				 * alloc_contig_range() will also lock the zone
-				 * at some point. If there's an allocation
-				 * spinning on this lock, it may win the race
-				 * and cause alloc_contig_range() to fail...
-				 */
-				spin_unlock_irqrestore(&zone->lock, flags);
-				ret = __alloc_gigantic_page(pfn, nr_pages, gfp_mask);
-				if (!ret)
-					return pfn_to_page(pfn);
-				spin_lock_irqsave(&zone->lock, flags);
-			}
-			pfn += nr_pages;
-		}
-
-		spin_unlock_irqrestore(&zone->lock, flags);
-	}
+	unsigned long nr_pages = 1UL << huge_page_order(h);
 
-	return NULL;
+	return alloc_contig_pages(nr_pages, gfp_mask, nid, nodemask);
 }
 
 static void prep_new_huge_page(struct hstate *h, struct page *page, int nid);
@@ -3915,7 +3796,7 @@ retry:
 			 * handling userfault.  Reacquire after handling
 			 * fault to make calling code simpler.
 			 */
-			hash = hugetlb_fault_mutex_hash(h, mapping, idx, haddr);
+			hash = hugetlb_fault_mutex_hash(mapping, idx);
 			mutex_unlock(&hugetlb_fault_mutex_table[hash]);
 			ret = handle_userfault(&vmf, VM_UFFD_MISSING);
 			mutex_lock(&hugetlb_fault_mutex_table[hash]);
@@ -4042,8 +3923,7 @@ backout_unlocked:
 }
 
 #ifdef CONFIG_SMP
-u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
-			    pgoff_t idx, unsigned long address)
+u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx)
 {
 	unsigned long key[2];
 	u32 hash;
@@ -4051,7 +3931,7 @@ u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
 	key[0] = (unsigned long) mapping;
 	key[1] = idx;
 
-	hash = jhash2((u32 *)&key, sizeof(key)/sizeof(u32), 0);
+	hash = jhash2((u32 *)&key, sizeof(key)/(sizeof(u32)), 0);
 
 	return hash & (num_fault_mutexes - 1);
 }
@@ -4060,8 +3940,7 @@ u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
  * For uniprocesor systems we always use a single mutex, so just
  * return 0 and avoid the hashing overhead.
  */
-u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
-			    pgoff_t idx, unsigned long address)
+u32 hugetlb_fault_mutex_hash(struct address_space *mapping, pgoff_t idx)
 {
 	return 0;
 }
@@ -4105,7 +3984,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 	 * get spurious allocation failures if two CPUs race to instantiate
 	 * the same page in the page cache.
 	 */
-	hash = hugetlb_fault_mutex_hash(h, mapping, idx, haddr);
+	hash = hugetlb_fault_mutex_hash(mapping, idx);
 	mutex_lock(&hugetlb_fault_mutex_table[hash]);
 
 	entry = huge_ptep_get(ptep);
@@ -4459,6 +4338,21 @@ long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
 				break;
 			}
 		}
+
+		/*
+		 * If subpage information not requested, update counters
+		 * and skip the same_page loop below.
+		 */
+		if (!pages && !vmas && !pfn_offset &&
+		    (vaddr + huge_page_size(h) < vma->vm_end) &&
+		    (remainder >= pages_per_huge_page(h))) {
+			vaddr += huge_page_size(h);
+			remainder -= pages_per_huge_page(h);
+			i += pages_per_huge_page(h);
+			spin_unlock(ptl);
+			continue;
+		}
+
 same_page:
 		if (pages) {
 			pages[i] = mem_map_offset(page, pfn_offset);
diff --git a/mm/internal.h b/mm/internal.h
index 0d5f720c75ab..3cf20ab3ca01 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -165,6 +165,9 @@ extern void post_alloc_hook(struct page *page, unsigned int order,
 					gfp_t gfp_flags);
 extern int user_min_free_kbytes;
 
+extern void zone_pcp_update(struct zone *zone);
+extern void zone_pcp_reset(struct zone *zone);
+
 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
 
 /*
@@ -290,7 +293,8 @@ static inline bool is_data_mapping(vm_flags_t flags)
 
 /* mm/util.c */
 void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
-		struct vm_area_struct *prev, struct rb_node *rb_parent);
+		struct vm_area_struct *prev);
+void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma);
 
 #ifdef CONFIG_MMU
 extern long populate_vma_page_range(struct vm_area_struct *vma,
@@ -362,6 +366,27 @@ vma_address(struct page *page, struct vm_area_struct *vma)
 	return max(start, vma->vm_start);
 }
 
+static inline struct file *maybe_unlock_mmap_for_io(struct vm_fault *vmf,
+						    struct file *fpin)
+{
+	int flags = vmf->flags;
+
+	if (fpin)
+		return fpin;
+
+	/*
+	 * FAULT_FLAG_RETRY_NOWAIT means we don't want to wait on page locks or
+	 * anything, so we only pin the file and drop the mmap_sem if only
+	 * FAULT_FLAG_ALLOW_RETRY is set.
+	 */
+	if ((flags & (FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_RETRY_NOWAIT)) ==
+	    FAULT_FLAG_ALLOW_RETRY) {
+		fpin = get_file(vmf->vma->vm_file);
+		up_read(&vmf->vma->vm_mm->mmap_sem);
+	}
+	return fpin;
+}
+
 #else /* !CONFIG_MMU */
 static inline void clear_page_mlock(struct page *page) { }
 static inline void mlock_vma_page(struct page *page) { }
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 0a1b4b484ac5..cd480dce92c6 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -1601,17 +1601,6 @@ static void collapse_file(struct mm_struct *mm,
 					result = SCAN_FAIL;
 					goto xa_unlocked;
 				}
-			} else if (!PageUptodate(page)) {
-				xas_unlock_irq(&xas);
-				wait_on_page_locked(page);
-				if (!trylock_page(page)) {
-					result = SCAN_PAGE_LOCK;
-					goto xa_unlocked;
-				}
-				get_page(page);
-			} else if (PageDirty(page)) {
-				result = SCAN_FAIL;
-				goto xa_locked;
 			} else if (trylock_page(page)) {
 				get_page(page);
 				xas_unlock_irq(&xas);
@@ -1626,7 +1615,12 @@ static void collapse_file(struct mm_struct *mm,
 		 * without racing with truncate.
 		 */
 		VM_BUG_ON_PAGE(!PageLocked(page), page);
-		VM_BUG_ON_PAGE(!PageUptodate(page), page);
+
+		/* double check the page is up to date */
+		if (unlikely(!PageUptodate(page))) {
+			result = SCAN_FAIL;
+			goto out_unlock;
+		}
 
 		/*
 		 * If file was truncated then extended, or hole-punched, before
@@ -1642,6 +1636,24 @@ static void collapse_file(struct mm_struct *mm,
 			goto out_unlock;
 		}
 
+		if (!is_shmem && PageDirty(page)) {
+			/*
+			 * khugepaged only works on read-only fd, so this
+			 * page is dirty because it hasn't been flushed
+			 * since first write. There won't be new dirty
+			 * pages.
+			 *
+			 * Trigger async flush here and hope the writeback
+			 * is done when khugepaged revisits this page.
+			 *
+			 * This is a one-off situation. We are not forcing
+			 * writeback in loop.
+			 */
+			filemap_flush(mapping);
+			result = SCAN_FAIL;
+			goto out_unlock;
+		}
+
 		if (isolate_lru_page(page)) {
 			result = SCAN_DEL_PAGE_LRU;
 			goto out_unlock;
diff --git a/mm/madvise.c b/mm/madvise.c
index 2be9f3fdb05e..99dd06fecfa9 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -887,7 +887,7 @@ static int madvise_inject_error(int behavior,
 			pr_info("Soft offlining pfn %#lx at process virtual address %#lx\n",
 					pfn, start);
 
-			ret = soft_offline_page(page, MF_COUNT_INCREASED);
+			ret = soft_offline_page(pfn, MF_COUNT_INCREASED);
 			if (ret)
 				return ret;
 			continue;
diff --git a/mm/memblock.c b/mm/memblock.c
index c4b16cae2bc9..1f84be7d2b7d 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1323,12 +1323,13 @@ __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
  * @start: the lower bound of the memory region to allocate (phys address)
  * @end: the upper bound of the memory region to allocate (phys address)
  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ * @exact_nid: control the allocation fall back to other nodes
  *
  * The allocation is performed from memory region limited by
  * memblock.current_limit if @max_addr == %MEMBLOCK_ALLOC_ACCESSIBLE.
  *
- * If the specified node can not hold the requested memory the
- * allocation falls back to any node in the system
+ * If the specified node can not hold the requested memory and @exact_nid
+ * is false, the allocation falls back to any node in the system
  *
  * For systems with memory mirroring, the allocation is attempted first
  * from the regions with mirroring enabled and then retried from any
@@ -1342,7 +1343,8 @@ __next_mem_pfn_range_in_zone(u64 *idx, struct zone *zone,
  */
 static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size,
 					phys_addr_t align, phys_addr_t start,
-					phys_addr_t end, int nid)
+					phys_addr_t end, int nid,
+					bool exact_nid)
 {
 	enum memblock_flags flags = choose_memblock_flags();
 	phys_addr_t found;
@@ -1362,7 +1364,7 @@ again:
 	if (found && !memblock_reserve(found, size))
 		goto done;
 
-	if (nid != NUMA_NO_NODE) {
+	if (nid != NUMA_NO_NODE && !exact_nid) {
 		found = memblock_find_in_range_node(size, align, start,
 						    end, NUMA_NO_NODE,
 						    flags);
@@ -1410,7 +1412,8 @@ phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
 					     phys_addr_t start,
 					     phys_addr_t end)
 {
-	return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE);
+	return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
+					false);
 }
 
 /**
@@ -1429,7 +1432,7 @@ phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
 phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
 {
 	return memblock_alloc_range_nid(size, align, 0,
-					MEMBLOCK_ALLOC_ACCESSIBLE, nid);
+					MEMBLOCK_ALLOC_ACCESSIBLE, nid, false);
 }
 
 /**
@@ -1439,6 +1442,7 @@ phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t ali
  * @min_addr: the lower bound of the memory region to allocate (phys address)
  * @max_addr: the upper bound of the memory region to allocate (phys address)
  * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ * @exact_nid: control the allocation fall back to other nodes
  *
  * Allocates memory block using memblock_alloc_range_nid() and
  * converts the returned physical address to virtual.
@@ -1454,7 +1458,7 @@ phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t ali
 static void * __init memblock_alloc_internal(
 				phys_addr_t size, phys_addr_t align,
 				phys_addr_t min_addr, phys_addr_t max_addr,
-				int nid)
+				int nid, bool exact_nid)
 {
 	phys_addr_t alloc;
 
@@ -1469,11 +1473,13 @@ static void * __init memblock_alloc_internal(
 	if (max_addr > memblock.current_limit)
 		max_addr = memblock.current_limit;
 
-	alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid);
+	alloc = memblock_alloc_range_nid(size, align, min_addr, max_addr, nid,
+					exact_nid);
 
 	/* retry allocation without lower limit */
 	if (!alloc && min_addr)
-		alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid);
+		alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid,
+						exact_nid);
 
 	if (!alloc)
 		return NULL;
@@ -1482,6 +1488,43 @@ static void * __init memblock_alloc_internal(
 }
 
 /**
+ * memblock_alloc_exact_nid_raw - allocate boot memory block on the exact node
+ * without zeroing memory
+ * @size: size of memory block to be allocated in bytes
+ * @align: alignment of the region and block's size
+ * @min_addr: the lower bound of the memory region from where the allocation
+ *	  is preferred (phys address)
+ * @max_addr: the upper bound of the memory region from where the allocation
+ *	      is preferred (phys address), or %MEMBLOCK_ALLOC_ACCESSIBLE to
+ *	      allocate only from memory limited by memblock.current_limit value
+ * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ *
+ * Public function, provides additional debug information (including caller
+ * info), if enabled. Does not zero allocated memory.
+ *
+ * Return:
+ * Virtual address of allocated memory block on success, NULL on failure.
+ */
+void * __init memblock_alloc_exact_nid_raw(
+			phys_addr_t size, phys_addr_t align,
+			phys_addr_t min_addr, phys_addr_t max_addr,
+			int nid)
+{
+	void *ptr;
+
+	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
+		     __func__, (u64)size, (u64)align, nid, &min_addr,
+		     &max_addr, (void *)_RET_IP_);
+
+	ptr = memblock_alloc_internal(size, align,
+					   min_addr, max_addr, nid, true);
+	if (ptr && size > 0)
+		page_init_poison(ptr, size);
+
+	return ptr;
+}
+
+/**
  * memblock_alloc_try_nid_raw - allocate boot memory block without zeroing
  * memory and without panicking
  * @size: size of memory block to be allocated in bytes
@@ -1512,7 +1555,7 @@ void * __init memblock_alloc_try_nid_raw(
 		     &max_addr, (void *)_RET_IP_);
 
 	ptr = memblock_alloc_internal(size, align,
-					   min_addr, max_addr, nid);
+					   min_addr, max_addr, nid, false);
 	if (ptr && size > 0)
 		page_init_poison(ptr, size);
 
@@ -1547,7 +1590,7 @@ void * __init memblock_alloc_try_nid(
 		     __func__, (u64)size, (u64)align, nid, &min_addr,
 		     &max_addr, (void *)_RET_IP_);
 	ptr = memblock_alloc_internal(size, align,
-					   min_addr, max_addr, nid);
+					   min_addr, max_addr, nid, false);
 	if (ptr)
 		memset(ptr, 0, size);
 
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 4b3865a1e4c1..ea085877c548 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -98,14 +98,6 @@ static bool do_memsw_account(void)
 	return !cgroup_subsys_on_dfl(memory_cgrp_subsys) && do_swap_account;
 }
 
-static const char *const mem_cgroup_lru_names[] = {
-	"inactive_anon",
-	"active_anon",
-	"inactive_file",
-	"active_file",
-	"unevictable",
-};
-
 #define THRESHOLDS_EVENTS_TARGET 128
 #define SOFTLIMIT_EVENTS_TARGET 1024
 #define NUMAINFO_EVENTS_TARGET	1024
@@ -1052,7 +1044,7 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root,
 		struct mem_cgroup_per_node *mz;
 
 		mz = mem_cgroup_nodeinfo(root, reclaim->pgdat->node_id);
-		iter = &mz->iter[reclaim->priority];
+		iter = &mz->iter;
 
 		if (prev && reclaim->generation != iter->generation)
 			goto out_unlock;
@@ -1152,15 +1144,11 @@ static void __invalidate_reclaim_iterators(struct mem_cgroup *from,
 	struct mem_cgroup_reclaim_iter *iter;
 	struct mem_cgroup_per_node *mz;
 	int nid;
-	int i;
 
 	for_each_node(nid) {
 		mz = mem_cgroup_nodeinfo(from, nid);
-		for (i = 0; i <= DEF_PRIORITY; i++) {
-			iter = &mz->iter[i];
-			cmpxchg(&iter->position,
-				dead_memcg, NULL);
-		}
+		iter = &mz->iter;
+		cmpxchg(&iter->position, dead_memcg, NULL);
 	}
 }
 
@@ -1438,7 +1426,7 @@ static char *memory_stat_format(struct mem_cgroup *memcg)
 		       PAGE_SIZE);
 
 	for (i = 0; i < NR_LRU_LISTS; i++)
-		seq_buf_printf(&s, "%s %llu\n", mem_cgroup_lru_names[i],
+		seq_buf_printf(&s, "%s %llu\n", lru_list_name(i),
 			       (u64)memcg_page_state(memcg, NR_LRU_BASE + i) *
 			       PAGE_SIZE);
 
@@ -1451,8 +1439,10 @@ static char *memory_stat_format(struct mem_cgroup *memcg)
 
 	/* Accumulated memory events */
 
-	seq_buf_printf(&s, "pgfault %lu\n", memcg_events(memcg, PGFAULT));
-	seq_buf_printf(&s, "pgmajfault %lu\n", memcg_events(memcg, PGMAJFAULT));
+	seq_buf_printf(&s, "%s %lu\n", vm_event_name(PGFAULT),
+		       memcg_events(memcg, PGFAULT));
+	seq_buf_printf(&s, "%s %lu\n", vm_event_name(PGMAJFAULT),
+		       memcg_events(memcg, PGMAJFAULT));
 
 	seq_buf_printf(&s, "workingset_refault %lu\n",
 		       memcg_page_state(memcg, WORKINGSET_REFAULT));
@@ -1461,22 +1451,27 @@ static char *memory_stat_format(struct mem_cgroup *memcg)
 	seq_buf_printf(&s, "workingset_nodereclaim %lu\n",
 		       memcg_page_state(memcg, WORKINGSET_NODERECLAIM));
 
-	seq_buf_printf(&s, "pgrefill %lu\n", memcg_events(memcg, PGREFILL));
+	seq_buf_printf(&s, "%s %lu\n",  vm_event_name(PGREFILL),
+		       memcg_events(memcg, PGREFILL));
 	seq_buf_printf(&s, "pgscan %lu\n",
 		       memcg_events(memcg, PGSCAN_KSWAPD) +
 		       memcg_events(memcg, PGSCAN_DIRECT));
 	seq_buf_printf(&s, "pgsteal %lu\n",
 		       memcg_events(memcg, PGSTEAL_KSWAPD) +
 		       memcg_events(memcg, PGSTEAL_DIRECT));
-	seq_buf_printf(&s, "pgactivate %lu\n", memcg_events(memcg, PGACTIVATE));
-	seq_buf_printf(&s, "pgdeactivate %lu\n", memcg_events(memcg, PGDEACTIVATE));
-	seq_buf_printf(&s, "pglazyfree %lu\n", memcg_events(memcg, PGLAZYFREE));
-	seq_buf_printf(&s, "pglazyfreed %lu\n", memcg_events(memcg, PGLAZYFREED));
+	seq_buf_printf(&s, "%s %lu\n", vm_event_name(PGACTIVATE),
+		       memcg_events(memcg, PGACTIVATE));
+	seq_buf_printf(&s, "%s %lu\n", vm_event_name(PGDEACTIVATE),
+		       memcg_events(memcg, PGDEACTIVATE));
+	seq_buf_printf(&s, "%s %lu\n", vm_event_name(PGLAZYFREE),
+		       memcg_events(memcg, PGLAZYFREE));
+	seq_buf_printf(&s, "%s %lu\n", vm_event_name(PGLAZYFREED),
+		       memcg_events(memcg, PGLAZYFREED));
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	seq_buf_printf(&s, "thp_fault_alloc %lu\n",
+	seq_buf_printf(&s, "%s %lu\n", vm_event_name(THP_FAULT_ALLOC),
 		       memcg_events(memcg, THP_FAULT_ALLOC));
-	seq_buf_printf(&s, "thp_collapse_alloc %lu\n",
+	seq_buf_printf(&s, "%s %lu\n", vm_event_name(THP_COLLAPSE_ALLOC),
 		       memcg_events(memcg, THP_COLLAPSE_ALLOC));
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
@@ -1705,7 +1700,6 @@ static int mem_cgroup_soft_reclaim(struct mem_cgroup *root_memcg,
 	unsigned long nr_scanned;
 	struct mem_cgroup_reclaim_cookie reclaim = {
 		.pgdat = pgdat,
-		.priority = 0,
 	};
 
 	excess = soft_limit_excess(root_memcg);
@@ -3849,13 +3843,6 @@ static const unsigned int memcg1_events[] = {
 	PGMAJFAULT,
 };
 
-static const char *const memcg1_event_names[] = {
-	"pgpgin",
-	"pgpgout",
-	"pgfault",
-	"pgmajfault",
-};
-
 static int memcg_stat_show(struct seq_file *m, void *v)
 {
 	struct mem_cgroup *memcg = mem_cgroup_from_seq(m);
@@ -3864,7 +3851,6 @@ static int memcg_stat_show(struct seq_file *m, void *v)
 	unsigned int i;
 
 	BUILD_BUG_ON(ARRAY_SIZE(memcg1_stat_names) != ARRAY_SIZE(memcg1_stats));
-	BUILD_BUG_ON(ARRAY_SIZE(mem_cgroup_lru_names) != NR_LRU_LISTS);
 
 	for (i = 0; i < ARRAY_SIZE(memcg1_stats); i++) {
 		if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account())
@@ -3875,11 +3861,11 @@ static int memcg_stat_show(struct seq_file *m, void *v)
 	}
 
 	for (i = 0; i < ARRAY_SIZE(memcg1_events); i++)
-		seq_printf(m, "%s %lu\n", memcg1_event_names[i],
+		seq_printf(m, "%s %lu\n", vm_event_name(memcg1_events[i]),
 			   memcg_events_local(memcg, memcg1_events[i]));
 
 	for (i = 0; i < NR_LRU_LISTS; i++)
-		seq_printf(m, "%s %lu\n", mem_cgroup_lru_names[i],
+		seq_printf(m, "%s %lu\n", lru_list_name(i),
 			   memcg_page_state_local(memcg, NR_LRU_BASE + i) *
 			   PAGE_SIZE);
 
@@ -3904,11 +3890,12 @@ static int memcg_stat_show(struct seq_file *m, void *v)
 	}
 
 	for (i = 0; i < ARRAY_SIZE(memcg1_events); i++)
-		seq_printf(m, "total_%s %llu\n", memcg1_event_names[i],
+		seq_printf(m, "total_%s %llu\n",
+			   vm_event_name(memcg1_events[i]),
 			   (u64)memcg_events(memcg, memcg1_events[i]));
 
 	for (i = 0; i < NR_LRU_LISTS; i++)
-		seq_printf(m, "total_%s %llu\n", mem_cgroup_lru_names[i],
+		seq_printf(m, "total_%s %llu\n", lru_list_name(i),
 			   (u64)memcg_page_state(memcg, NR_LRU_BASE + i) *
 			   PAGE_SIZE);
 
@@ -5014,12 +5001,6 @@ static void __mem_cgroup_free(struct mem_cgroup *memcg)
 {
 	int node;
 
-	/*
-	 * Flush percpu vmstats and vmevents to guarantee the value correctness
-	 * on parent's and all ancestor levels.
-	 */
-	memcg_flush_percpu_vmstats(memcg, false);
-	memcg_flush_percpu_vmevents(memcg);
 	for_each_node(node)
 		free_mem_cgroup_per_node_info(memcg, node);
 	free_percpu(memcg->vmstats_percpu);
@@ -5030,6 +5011,12 @@ static void __mem_cgroup_free(struct mem_cgroup *memcg)
 static void mem_cgroup_free(struct mem_cgroup *memcg)
 {
 	memcg_wb_domain_exit(memcg);
+	/*
+	 * Flush percpu vmstats and vmevents to guarantee the value correctness
+	 * on parent's and all ancestor levels.
+	 */
+	memcg_flush_percpu_vmstats(memcg, false);
+	memcg_flush_percpu_vmevents(memcg);
 	__mem_cgroup_free(memcg);
 }
 
@@ -6087,7 +6074,8 @@ static ssize_t memory_high_write(struct kernfs_open_file *of,
 				 char *buf, size_t nbytes, loff_t off)
 {
 	struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
-	unsigned long nr_pages;
+	unsigned int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
+	bool drained = false;
 	unsigned long high;
 	int err;
 
@@ -6098,12 +6086,29 @@ static ssize_t memory_high_write(struct kernfs_open_file *of,
 
 	memcg->high = high;
 
-	nr_pages = page_counter_read(&memcg->memory);
-	if (nr_pages > high)
-		try_to_free_mem_cgroup_pages(memcg, nr_pages - high,
-					     GFP_KERNEL, true);
+	for (;;) {
+		unsigned long nr_pages = page_counter_read(&memcg->memory);
+		unsigned long reclaimed;
+
+		if (nr_pages <= high)
+			break;
+
+		if (signal_pending(current))
+			break;
+
+		if (!drained) {
+			drain_all_stock(memcg);
+			drained = true;
+			continue;
+		}
+
+		reclaimed = try_to_free_mem_cgroup_pages(memcg, nr_pages - high,
+							 GFP_KERNEL, true);
+
+		if (!reclaimed && !nr_retries--)
+			break;
+	}
 
-	memcg_wb_domain_size_changed(memcg);
 	return nbytes;
 }
 
@@ -6135,10 +6140,8 @@ static ssize_t memory_max_write(struct kernfs_open_file *of,
 		if (nr_pages <= max)
 			break;
 
-		if (signal_pending(current)) {
-			err = -EINTR;
+		if (signal_pending(current))
 			break;
-		}
 
 		if (!drained) {
 			drain_all_stock(memcg);
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 3151c87dff73..af2712004a4d 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -303,25 +303,19 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page,
 /*
  * Schedule a process for later kill.
  * Uses GFP_ATOMIC allocations to avoid potential recursions in the VM.
- * TBD would GFP_NOIO be enough?
  */
 static void add_to_kill(struct task_struct *tsk, struct page *p,
 		       struct vm_area_struct *vma,
-		       struct list_head *to_kill,
-		       struct to_kill **tkc)
+		       struct list_head *to_kill)
 {
 	struct to_kill *tk;
 
-	if (*tkc) {
-		tk = *tkc;
-		*tkc = NULL;
-	} else {
-		tk = kmalloc(sizeof(struct to_kill), GFP_ATOMIC);
-		if (!tk) {
-			pr_err("Memory failure: Out of memory while machine check handling\n");
-			return;
-		}
+	tk = kmalloc(sizeof(struct to_kill), GFP_ATOMIC);
+	if (!tk) {
+		pr_err("Memory failure: Out of memory while machine check handling\n");
+		return;
 	}
+
 	tk->addr = page_address_in_vma(p, vma);
 	if (is_zone_device_page(p))
 		tk->size_shift = dev_pagemap_mapping_shift(p, vma);
@@ -345,6 +339,7 @@ static void add_to_kill(struct task_struct *tsk, struct page *p,
 		kfree(tk);
 		return;
 	}
+
 	get_task_struct(tsk);
 	tk->tsk = tsk;
 	list_add_tail(&tk->nd, to_kill);
@@ -436,7 +431,7 @@ static struct task_struct *task_early_kill(struct task_struct *tsk,
  * Collect processes when the error hit an anonymous page.
  */
 static void collect_procs_anon(struct page *page, struct list_head *to_kill,
-			      struct to_kill **tkc, int force_early)
+				int force_early)
 {
 	struct vm_area_struct *vma;
 	struct task_struct *tsk;
@@ -461,7 +456,7 @@ static void collect_procs_anon(struct page *page, struct list_head *to_kill,
 			if (!page_mapped_in_vma(page, vma))
 				continue;
 			if (vma->vm_mm == t->mm)
-				add_to_kill(t, page, vma, to_kill, tkc);
+				add_to_kill(t, page, vma, to_kill);
 		}
 	}
 	read_unlock(&tasklist_lock);
@@ -472,7 +467,7 @@ static void collect_procs_anon(struct page *page, struct list_head *to_kill,
  * Collect processes when the error hit a file mapped page.
  */
 static void collect_procs_file(struct page *page, struct list_head *to_kill,
-			      struct to_kill **tkc, int force_early)
+				int force_early)
 {
 	struct vm_area_struct *vma;
 	struct task_struct *tsk;
@@ -496,7 +491,7 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill,
 			 * to be informed of all such data corruptions.
 			 */
 			if (vma->vm_mm == t->mm)
-				add_to_kill(t, page, vma, to_kill, tkc);
+				add_to_kill(t, page, vma, to_kill);
 		}
 	}
 	read_unlock(&tasklist_lock);
@@ -505,26 +500,17 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill,
 
 /*
  * Collect the processes who have the corrupted page mapped to kill.
- * This is done in two steps for locking reasons.
- * First preallocate one tokill structure outside the spin locks,
- * so that we can kill at least one process reasonably reliable.
  */
 static void collect_procs(struct page *page, struct list_head *tokill,
 				int force_early)
 {
-	struct to_kill *tk;
-
 	if (!page->mapping)
 		return;
 
-	tk = kmalloc(sizeof(struct to_kill), GFP_NOIO);
-	if (!tk)
-		return;
 	if (PageAnon(page))
-		collect_procs_anon(page, tokill, &tk, force_early);
+		collect_procs_anon(page, tokill, force_early);
 	else
-		collect_procs_file(page, tokill, &tk, force_early);
-	kfree(tk);
+		collect_procs_file(page, tokill, force_early);
 }
 
 static const char *action_name[] = {
@@ -1490,7 +1476,7 @@ static void memory_failure_work_func(struct work_struct *work)
 		if (!gotten)
 			break;
 		if (entry.flags & MF_SOFT_OFFLINE)
-			soft_offline_page(pfn_to_page(entry.pfn), entry.flags);
+			soft_offline_page(entry.pfn, entry.flags);
 		else
 			memory_failure(entry.pfn, entry.flags);
 	}
@@ -1871,7 +1857,7 @@ static int soft_offline_free_page(struct page *page)
 
 /**
  * soft_offline_page - Soft offline a page.
- * @page: page to offline
+ * @pfn: pfn to soft-offline
  * @flags: flags. Same as memory_failure().
  *
  * Returns 0 on success, otherwise negated errno.
@@ -1891,18 +1877,17 @@ static int soft_offline_free_page(struct page *page)
  * This is not a 100% solution for all memory, but tries to be
  * ``good enough'' for the majority of memory.
  */
-int soft_offline_page(struct page *page, int flags)
+int soft_offline_page(unsigned long pfn, int flags)
 {
 	int ret;
-	unsigned long pfn = page_to_pfn(page);
+	struct page *page;
 
-	if (is_zone_device_page(page)) {
-		pr_debug_ratelimited("soft_offline: %#lx page is device page\n",
-				pfn);
-		if (flags & MF_COUNT_INCREASED)
-			put_page(page);
+	if (!pfn_valid(pfn))
+		return -ENXIO;
+	/* Only online pages can be soft-offlined (esp., not ZONE_DEVICE). */
+	page = pfn_to_online_page(pfn);
+	if (!page)
 		return -EIO;
-	}
 
 	if (PageHWPoison(page)) {
 		pr_info("soft offline: %#lx page already poisoned\n", pfn);
diff --git a/mm/memory.c b/mm/memory.c
index b6a5d6a08438..7596d625ebd1 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -72,6 +72,8 @@
 #include <linux/oom.h>
 #include <linux/numa.h>
 
+#include <trace/events/kmem.h>
+
 #include <asm/io.h>
 #include <asm/mmu_context.h>
 #include <asm/pgalloc.h>
@@ -152,6 +154,10 @@ static int __init init_zero_pfn(void)
 }
 core_initcall(init_zero_pfn);
 
+void mm_trace_rss_stat(int member, long count)
+{
+	trace_rss_stat(member, count);
+}
 
 #if defined(SPLIT_RSS_COUNTING)
 
@@ -2289,10 +2295,11 @@ static vm_fault_t do_page_mkwrite(struct vm_fault *vmf)
  *
  * The function expects the page to be locked and unlocks it.
  */
-static void fault_dirty_shared_page(struct vm_area_struct *vma,
-				    struct page *page)
+static vm_fault_t fault_dirty_shared_page(struct vm_fault *vmf)
 {
+	struct vm_area_struct *vma = vmf->vma;
 	struct address_space *mapping;
+	struct page *page = vmf->page;
 	bool dirtied;
 	bool page_mkwrite = vma->vm_ops && vma->vm_ops->page_mkwrite;
 
@@ -2307,16 +2314,30 @@ static void fault_dirty_shared_page(struct vm_area_struct *vma,
 	mapping = page_rmapping(page);
 	unlock_page(page);
 
+	if (!page_mkwrite)
+		file_update_time(vma->vm_file);
+
+	/*
+	 * Throttle page dirtying rate down to writeback speed.
+	 *
+	 * mapping may be NULL here because some device drivers do not
+	 * set page.mapping but still dirty their pages
+	 *
+	 * Drop the mmap_sem before waiting on IO, if we can. The file
+	 * is pinning the mapping, as per above.
+	 */
 	if ((dirtied || page_mkwrite) && mapping) {
-		/*
-		 * Some device drivers do not set page.mapping
-		 * but still dirty their pages
-		 */
+		struct file *fpin;
+
+		fpin = maybe_unlock_mmap_for_io(vmf, NULL);
 		balance_dirty_pages_ratelimited(mapping);
+		if (fpin) {
+			fput(fpin);
+			return VM_FAULT_RETRY;
+		}
 	}
 
-	if (!page_mkwrite)
-		file_update_time(vma->vm_file);
+	return 0;
 }
 
 /*
@@ -2571,6 +2592,7 @@ static vm_fault_t wp_page_shared(struct vm_fault *vmf)
 	__releases(vmf->ptl)
 {
 	struct vm_area_struct *vma = vmf->vma;
+	vm_fault_t ret = VM_FAULT_WRITE;
 
 	get_page(vmf->page);
 
@@ -2594,10 +2616,10 @@ static vm_fault_t wp_page_shared(struct vm_fault *vmf)
 		wp_page_reuse(vmf);
 		lock_page(vmf->page);
 	}
-	fault_dirty_shared_page(vma, vmf->page);
+	ret |= fault_dirty_shared_page(vmf);
 	put_page(vmf->page);
 
-	return VM_FAULT_WRITE;
+	return ret;
 }
 
 /*
@@ -3083,7 +3105,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf)
 
 	/*
 	 * The memory barrier inside __SetPageUptodate makes sure that
-	 * preceeding stores to the page contents become visible before
+	 * preceding stores to the page contents become visible before
 	 * the set_pte_at() write.
 	 */
 	__SetPageUptodate(page);
@@ -3641,7 +3663,7 @@ static vm_fault_t do_shared_fault(struct vm_fault *vmf)
 		return ret;
 	}
 
-	fault_dirty_shared_page(vma, vmf->page);
+	ret |= fault_dirty_shared_page(vmf);
 	return ret;
 }
 
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index df570e5c71cc..561371ead39a 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -49,8 +49,6 @@
  * and restore_online_page_callback() for generic callback restore.
  */
 
-static void generic_online_page(struct page *page, unsigned int order);
-
 static online_page_callback_t online_page_callback = generic_online_page;
 static DEFINE_MUTEX(online_page_callback_lock);
 
@@ -278,6 +276,22 @@ static int check_pfn_span(unsigned long pfn, unsigned long nr_pages,
 	return 0;
 }
 
+static int check_hotplug_memory_addressable(unsigned long pfn,
+					    unsigned long nr_pages)
+{
+	const u64 max_addr = PFN_PHYS(pfn + nr_pages) - 1;
+
+	if (max_addr >> MAX_PHYSMEM_BITS) {
+		const u64 max_allowed = (1ull << (MAX_PHYSMEM_BITS + 1)) - 1;
+		WARN(1,
+		     "Hotplugged memory exceeds maximum addressable address, range=%#llx-%#llx, maximum=%#llx\n",
+		     (u64)PFN_PHYS(pfn), max_addr, max_allowed);
+		return -E2BIG;
+	}
+
+	return 0;
+}
+
 /*
  * Reasonably generic function for adding memory.  It is
  * expected that archs that support memory hotplug will
@@ -291,6 +305,10 @@ int __ref __add_pages(int nid, unsigned long pfn, unsigned long nr_pages,
 	unsigned long nr, start_sec, end_sec;
 	struct vmem_altmap *altmap = restrictions->altmap;
 
+	err = check_hotplug_memory_addressable(pfn, nr_pages);
+	if (err)
+		return err;
+
 	if (altmap) {
 		/*
 		 * Validate altmap is within bounds of the total request
@@ -331,13 +349,13 @@ static unsigned long find_smallest_section_pfn(int nid, struct zone *zone,
 				     unsigned long end_pfn)
 {
 	for (; start_pfn < end_pfn; start_pfn += PAGES_PER_SUBSECTION) {
-		if (unlikely(!pfn_valid(start_pfn)))
+		if (unlikely(!pfn_to_online_page(start_pfn)))
 			continue;
 
 		if (unlikely(pfn_to_nid(start_pfn) != nid))
 			continue;
 
-		if (zone && zone != page_zone(pfn_to_page(start_pfn)))
+		if (zone != page_zone(pfn_to_page(start_pfn)))
 			continue;
 
 		return start_pfn;
@@ -356,13 +374,13 @@ static unsigned long find_biggest_section_pfn(int nid, struct zone *zone,
 	/* pfn is the end pfn of a memory section. */
 	pfn = end_pfn - 1;
 	for (; pfn >= start_pfn; pfn -= PAGES_PER_SUBSECTION) {
-		if (unlikely(!pfn_valid(pfn)))
+		if (unlikely(!pfn_to_online_page(pfn)))
 			continue;
 
 		if (unlikely(pfn_to_nid(pfn) != nid))
 			continue;
 
-		if (zone && zone != page_zone(pfn_to_page(pfn)))
+		if (zone != page_zone(pfn_to_page(pfn)))
 			continue;
 
 		return pfn;
@@ -374,14 +392,11 @@ static unsigned long find_biggest_section_pfn(int nid, struct zone *zone,
 static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
 			     unsigned long end_pfn)
 {
-	unsigned long zone_start_pfn = zone->zone_start_pfn;
-	unsigned long z = zone_end_pfn(zone); /* zone_end_pfn namespace clash */
-	unsigned long zone_end_pfn = z;
 	unsigned long pfn;
 	int nid = zone_to_nid(zone);
 
 	zone_span_writelock(zone);
-	if (zone_start_pfn == start_pfn) {
+	if (zone->zone_start_pfn == start_pfn) {
 		/*
 		 * If the section is smallest section in the zone, it need
 		 * shrink zone->zone_start_pfn and zone->zone_spanned_pages.
@@ -389,50 +404,30 @@ static void shrink_zone_span(struct zone *zone, unsigned long start_pfn,
 		 * for shrinking zone.
 		 */
 		pfn = find_smallest_section_pfn(nid, zone, end_pfn,
-						zone_end_pfn);
+						zone_end_pfn(zone));
 		if (pfn) {
+			zone->spanned_pages = zone_end_pfn(zone) - pfn;
 			zone->zone_start_pfn = pfn;
-			zone->spanned_pages = zone_end_pfn - pfn;
+		} else {
+			zone->zone_start_pfn = 0;
+			zone->spanned_pages = 0;
 		}
-	} else if (zone_end_pfn == end_pfn) {
+	} else if (zone_end_pfn(zone) == end_pfn) {
 		/*
 		 * If the section is biggest section in the zone, it need
 		 * shrink zone->spanned_pages.
 		 * In this case, we find second biggest valid mem_section for
 		 * shrinking zone.
 		 */
-		pfn = find_biggest_section_pfn(nid, zone, zone_start_pfn,
+		pfn = find_biggest_section_pfn(nid, zone, zone->zone_start_pfn,
 					       start_pfn);
 		if (pfn)
-			zone->spanned_pages = pfn - zone_start_pfn + 1;
-	}
-
-	/*
-	 * The section is not biggest or smallest mem_section in the zone, it
-	 * only creates a hole in the zone. So in this case, we need not
-	 * change the zone. But perhaps, the zone has only hole data. Thus
-	 * it check the zone has only hole or not.
-	 */
-	pfn = zone_start_pfn;
-	for (; pfn < zone_end_pfn; pfn += PAGES_PER_SUBSECTION) {
-		if (unlikely(!pfn_valid(pfn)))
-			continue;
-
-		if (page_zone(pfn_to_page(pfn)) != zone)
-			continue;
-
-		/* Skip range to be removed */
-		if (pfn >= start_pfn && pfn < end_pfn)
-			continue;
-
-		/* If we find valid section, we have nothing to do */
-		zone_span_writeunlock(zone);
-		return;
+			zone->spanned_pages = pfn - zone->zone_start_pfn + 1;
+		else {
+			zone->zone_start_pfn = 0;
+			zone->spanned_pages = 0;
+		}
 	}
-
-	/* The zone has no valid section */
-	zone->zone_start_pfn = 0;
-	zone->spanned_pages = 0;
 	zone_span_writeunlock(zone);
 }
 
@@ -457,34 +452,50 @@ static void update_pgdat_span(struct pglist_data *pgdat)
 	pgdat->node_spanned_pages = node_end_pfn - node_start_pfn;
 }
 
-static void __remove_zone(struct zone *zone, unsigned long start_pfn,
-		unsigned long nr_pages)
+void __ref remove_pfn_range_from_zone(struct zone *zone,
+				      unsigned long start_pfn,
+				      unsigned long nr_pages)
 {
 	struct pglist_data *pgdat = zone->zone_pgdat;
 	unsigned long flags;
 
+	/* Poison struct pages because they are now uninitialized again. */
+	page_init_poison(pfn_to_page(start_pfn), sizeof(struct page) * nr_pages);
+
+#ifdef CONFIG_ZONE_DEVICE
+	/*
+	 * Zone shrinking code cannot properly deal with ZONE_DEVICE. So
+	 * we will not try to shrink the zones - which is okay as
+	 * set_zone_contiguous() cannot deal with ZONE_DEVICE either way.
+	 */
+	if (zone_idx(zone) == ZONE_DEVICE)
+		return;
+#endif
+
+	clear_zone_contiguous(zone);
+
 	pgdat_resize_lock(zone->zone_pgdat, &flags);
 	shrink_zone_span(zone, start_pfn, start_pfn + nr_pages);
 	update_pgdat_span(pgdat);
 	pgdat_resize_unlock(zone->zone_pgdat, &flags);
+
+	set_zone_contiguous(zone);
 }
 
-static void __remove_section(struct zone *zone, unsigned long pfn,
-		unsigned long nr_pages, unsigned long map_offset,
-		struct vmem_altmap *altmap)
+static void __remove_section(unsigned long pfn, unsigned long nr_pages,
+			     unsigned long map_offset,
+			     struct vmem_altmap *altmap)
 {
 	struct mem_section *ms = __nr_to_section(pfn_to_section_nr(pfn));
 
 	if (WARN_ON_ONCE(!valid_section(ms)))
 		return;
 
-	__remove_zone(zone, pfn, nr_pages);
 	sparse_remove_section(ms, pfn, nr_pages, map_offset, altmap);
 }
 
 /**
- * __remove_pages() - remove sections of pages from a zone
- * @zone: zone from which pages need to be removed
+ * __remove_pages() - remove sections of pages
  * @pfn: starting pageframe (must be aligned to start of a section)
  * @nr_pages: number of pages to remove (must be multiple of section size)
  * @altmap: alternative device page map or %NULL if default memmap is used
@@ -494,34 +505,25 @@ static void __remove_section(struct zone *zone, unsigned long pfn,
  * sure that pages are marked reserved and zones are adjust properly by
  * calling offline_pages().
  */
-void __remove_pages(struct zone *zone, unsigned long pfn,
-		    unsigned long nr_pages, struct vmem_altmap *altmap)
+void __remove_pages(unsigned long pfn, unsigned long nr_pages,
+		    struct vmem_altmap *altmap)
 {
+	const unsigned long end_pfn = pfn + nr_pages;
+	unsigned long cur_nr_pages;
 	unsigned long map_offset = 0;
-	unsigned long nr, start_sec, end_sec;
 
 	map_offset = vmem_altmap_offset(altmap);
 
-	clear_zone_contiguous(zone);
-
 	if (check_pfn_span(pfn, nr_pages, "remove"))
 		return;
 
-	start_sec = pfn_to_section_nr(pfn);
-	end_sec = pfn_to_section_nr(pfn + nr_pages - 1);
-	for (nr = start_sec; nr <= end_sec; nr++) {
-		unsigned long pfns;
-
+	for (; pfn < end_pfn; pfn += cur_nr_pages) {
 		cond_resched();
-		pfns = min(nr_pages, PAGES_PER_SECTION
-				- (pfn & ~PAGE_SECTION_MASK));
-		__remove_section(zone, pfn, pfns, map_offset, altmap);
-		pfn += pfns;
-		nr_pages -= pfns;
+		/* Select all remaining pages up to the next section boundary */
+		cur_nr_pages = min(end_pfn - pfn, -(pfn | PAGE_SECTION_MASK));
+		__remove_section(pfn, cur_nr_pages, map_offset, altmap);
 		map_offset = 0;
 	}
-
-	set_zone_contiguous(zone);
 }
 
 int set_online_page_callback(online_page_callback_t callback)
@@ -562,24 +564,7 @@ int restore_online_page_callback(online_page_callback_t callback)
 }
 EXPORT_SYMBOL_GPL(restore_online_page_callback);
 
-void __online_page_set_limits(struct page *page)
-{
-}
-EXPORT_SYMBOL_GPL(__online_page_set_limits);
-
-void __online_page_increment_counters(struct page *page)
-{
-	adjust_managed_page_count(page, 1);
-}
-EXPORT_SYMBOL_GPL(__online_page_increment_counters);
-
-void __online_page_free(struct page *page)
-{
-	__free_reserved_page(page);
-}
-EXPORT_SYMBOL_GPL(__online_page_free);
-
-static void generic_online_page(struct page *page, unsigned int order)
+void generic_online_page(struct page *page, unsigned int order)
 {
 	kernel_map_pages(page, 1 << order, 1);
 	__free_pages_core(page, order);
@@ -589,6 +574,7 @@ static void generic_online_page(struct page *page, unsigned int order)
 		totalhigh_pages_add(1UL << order);
 #endif
 }
+EXPORT_SYMBOL_GPL(generic_online_page);
 
 static int online_pages_range(unsigned long start_pfn, unsigned long nr_pages,
 			void *arg)
@@ -849,6 +835,7 @@ failed_addition:
 		 (unsigned long long) pfn << PAGE_SHIFT,
 		 (((unsigned long long) pfn + nr_pages) << PAGE_SHIFT) - 1);
 	memory_notify(MEM_CANCEL_ONLINE, &arg);
+	remove_pfn_range_from_zone(zone, pfn, nr_pages);
 	mem_hotplug_done();
 	return ret;
 }
@@ -1162,7 +1149,8 @@ static bool is_pageblock_removable_nolock(unsigned long pfn)
 	if (!zone_spans_pfn(zone, pfn))
 		return false;
 
-	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE, SKIP_HWPOISON);
+	return !has_unmovable_pages(zone, page, 0, MIGRATE_MOVABLE,
+				    MEMORY_OFFLINE);
 }
 
 /* Checks if this range of memory is likely to be hot-removable. */
@@ -1359,9 +1347,7 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 	return ret;
 }
 
-/*
- * remove from free_area[] and mark all as Reserved.
- */
+/* Mark all sections offline and remove all free pages from the buddy. */
 static int
 offline_isolated_pages_cb(unsigned long start, unsigned long nr_pages,
 			void *data)
@@ -1379,7 +1365,8 @@ static int
 check_pages_isolated_cb(unsigned long start_pfn, unsigned long nr_pages,
 			void *data)
 {
-	return test_pages_isolated(start_pfn, start_pfn + nr_pages, true);
+	return test_pages_isolated(start_pfn, start_pfn + nr_pages,
+				   MEMORY_OFFLINE);
 }
 
 static int __init cmdline_parse_movable_node(char *p)
@@ -1490,7 +1477,7 @@ static int __ref __offline_pages(unsigned long start_pfn,
 	/* set above range as isolated */
 	ret = start_isolate_page_range(start_pfn, end_pfn,
 				       MIGRATE_MOVABLE,
-				       SKIP_HWPOISON | REPORT_FAILURE);
+				       MEMORY_OFFLINE | REPORT_FAILURE);
 	if (ret < 0) {
 		reason = "failure to isolate range";
 		goto failed_removal;
@@ -1584,6 +1571,7 @@ static int __ref __offline_pages(unsigned long start_pfn,
 	writeback_set_ratelimit();
 
 	memory_notify(MEM_OFFLINE, &arg);
+	remove_pfn_range_from_zone(zone, start_pfn, nr_pages);
 	mem_hotplug_done();
 	return 0;
 
@@ -1721,13 +1709,13 @@ static int __ref try_remove_memory(int nid, u64 start, u64 size)
 
 	/* remove memmap entry */
 	firmware_map_remove(start, start + size, "System RAM");
-	memblock_free(start, size);
-	memblock_remove(start, size);
 
 	/* remove memory block devices before removing memory */
 	remove_memory_block_devices(start, size);
 
 	arch_remove_memory(nid, start, size, NULL);
+	memblock_free(start, size);
+	memblock_remove(start, size);
 	__release_memory_resource(start, size);
 
 	try_offline_node(nid);
diff --git a/mm/memremap.c b/mm/memremap.c
index 03ccbdfeb697..022e78e68ea0 100644
--- a/mm/memremap.c
+++ b/mm/memremap.c
@@ -55,8 +55,16 @@ static void pgmap_array_delete(struct resource *res)
 
 static unsigned long pfn_first(struct dev_pagemap *pgmap)
 {
-	return PHYS_PFN(pgmap->res.start) +
-		vmem_altmap_offset(pgmap_altmap(pgmap));
+	const struct resource *res = &pgmap->res;
+	struct vmem_altmap *altmap = pgmap_altmap(pgmap);
+	unsigned long pfn;
+
+	if (altmap)
+		pfn = altmap->base_pfn + vmem_altmap_offset(altmap);
+	else
+		pfn = PHYS_PFN(res->start);
+
+	return pfn;
 }
 
 static unsigned long pfn_end(struct dev_pagemap *pgmap)
@@ -73,6 +81,26 @@ static unsigned long pfn_next(unsigned long pfn)
 	return pfn + 1;
 }
 
+/*
+ * This returns true if the page is reserved by ZONE_DEVICE driver.
+ */
+bool pfn_zone_device_reserved(unsigned long pfn)
+{
+	struct dev_pagemap *pgmap;
+	struct vmem_altmap *altmap;
+	bool ret = false;
+
+	pgmap = get_dev_pagemap(pfn, NULL);
+	if (!pgmap)
+		return ret;
+	altmap = pgmap_altmap(pgmap);
+	if (altmap && pfn < (altmap->base_pfn + altmap->reserve))
+		ret = true;
+	put_dev_pagemap(pgmap);
+
+	return ret;
+}
+
 #define for_each_device_pfn(pfn, map) \
 	for (pfn = pfn_first(map); pfn < pfn_end(map); pfn = pfn_next(pfn))
 
@@ -119,8 +147,10 @@ void memunmap_pages(struct dev_pagemap *pgmap)
 	nid = page_to_nid(first_page);
 
 	mem_hotplug_begin();
+	remove_pfn_range_from_zone(page_zone(first_page), PHYS_PFN(res->start),
+				   PHYS_PFN(resource_size(res)));
 	if (pgmap->type == MEMORY_DEVICE_PRIVATE) {
-		__remove_pages(page_zone(first_page), PHYS_PFN(res->start),
+		__remove_pages(PHYS_PFN(res->start),
 			       PHYS_PFN(resource_size(res)), NULL);
 	} else {
 		arch_remove_memory(nid, res->start, resource_size(res),
diff --git a/mm/mmap.c b/mm/mmap.c
index a7d8c84d19b7..d5ca73facd5d 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -641,7 +641,7 @@ __vma_link(struct mm_struct *mm, struct vm_area_struct *vma,
 	struct vm_area_struct *prev, struct rb_node **rb_link,
 	struct rb_node *rb_parent)
 {
-	__vma_link_list(mm, vma, prev, rb_parent);
+	__vma_link_list(mm, vma, prev);
 	__vma_link_rb(mm, vma, rb_link, rb_parent);
 }
 
@@ -684,37 +684,14 @@ static void __insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
 
 static __always_inline void __vma_unlink_common(struct mm_struct *mm,
 						struct vm_area_struct *vma,
-						struct vm_area_struct *prev,
-						bool has_prev,
 						struct vm_area_struct *ignore)
 {
-	struct vm_area_struct *next;
-
 	vma_rb_erase_ignore(vma, &mm->mm_rb, ignore);
-	next = vma->vm_next;
-	if (has_prev)
-		prev->vm_next = next;
-	else {
-		prev = vma->vm_prev;
-		if (prev)
-			prev->vm_next = next;
-		else
-			mm->mmap = next;
-	}
-	if (next)
-		next->vm_prev = prev;
-
+	__vma_unlink_list(mm, vma);
 	/* Kill the cache */
 	vmacache_invalidate(mm);
 }
 
-static inline void __vma_unlink_prev(struct mm_struct *mm,
-				     struct vm_area_struct *vma,
-				     struct vm_area_struct *prev)
-{
-	__vma_unlink_common(mm, vma, prev, true, vma);
-}
-
 /*
  * We cannot adjust vm_start, vm_end, vm_pgoff fields of a vma that
  * is already present in an i_mmap tree without adjusting the tree.
@@ -769,8 +746,6 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
 				remove_next = 1 + (end > next->vm_end);
 				VM_WARN_ON(remove_next == 2 &&
 					   end != next->vm_next->vm_end);
-				VM_WARN_ON(remove_next == 1 &&
-					   end != next->vm_end);
 				/* trim end to next, for case 6 first pass */
 				end = next->vm_end;
 			}
@@ -889,7 +864,7 @@ again:
 		 * us to remove next before dropping the locks.
 		 */
 		if (remove_next != 3)
-			__vma_unlink_prev(mm, next, vma);
+			__vma_unlink_common(mm, next, next);
 		else
 			/*
 			 * vma is not before next if they've been
@@ -900,7 +875,7 @@ again:
 			 * "next" (which is stored in post-swap()
 			 * "vma").
 			 */
-			__vma_unlink_common(mm, next, NULL, false, vma);
+			__vma_unlink_common(mm, next, vma);
 		if (file)
 			__remove_shared_vm_struct(next, file, mapping);
 	} else if (insert) {
@@ -1442,7 +1417,7 @@ unsigned long do_mmap(struct file *file, unsigned long addr,
 	 * that it represents a valid section of the address space.
 	 */
 	addr = get_unmapped_area(file, addr, len, pgoff, flags);
-	if (offset_in_page(addr))
+	if (IS_ERR_VALUE(addr))
 		return addr;
 
 	if (flags & MAP_FIXED_NOREPLACE) {
@@ -1884,6 +1859,22 @@ unacct_error:
 	return error;
 }
 
+static inline unsigned long gap_start_offset(struct vm_unmapped_area_info *info,
+					unsigned long addr)
+{
+	/* get gap_start offset to adjust gap address to the
+	 * desired alignment
+	 */
+	return (info->align_offset - addr) & info->align_mask;
+}
+
+static inline unsigned long gap_end_offset(struct vm_unmapped_area_info *info,
+					unsigned long addr)
+{
+	/* get gap_end offset to adjust gap address to the desired alignment */
+	return (addr - info->align_offset) & info->align_mask;
+}
+
 unsigned long unmapped_area(struct vm_unmapped_area_info *info)
 {
 	/*
@@ -1898,10 +1889,7 @@ unsigned long unmapped_area(struct vm_unmapped_area_info *info)
 	struct vm_area_struct *vma;
 	unsigned long length, low_limit, high_limit, gap_start, gap_end;
 
-	/* Adjust search length to account for worst case alignment overhead */
-	length = info->length + info->align_mask;
-	if (length < info->length)
-		return -ENOMEM;
+	length = info->length;
 
 	/* Adjust search limits by the desired length */
 	if (info->high_limit < length)
@@ -1933,6 +1921,7 @@ unsigned long unmapped_area(struct vm_unmapped_area_info *info)
 		}
 
 		gap_start = vma->vm_prev ? vm_end_gap(vma->vm_prev) : 0;
+		gap_start += gap_start_offset(info, gap_start);
 check_current:
 		/* Check if current node has a suitable gap */
 		if (gap_start > high_limit)
@@ -1961,6 +1950,7 @@ check_current:
 				       struct vm_area_struct, vm_rb);
 			if (prev == vma->vm_rb.rb_left) {
 				gap_start = vm_end_gap(vma->vm_prev);
+				gap_start += gap_start_offset(info, gap_start);
 				gap_end = vm_start_gap(vma);
 				goto check_current;
 			}
@@ -1970,17 +1960,17 @@ check_current:
 check_highest:
 	/* Check highest gap, which does not precede any rbtree node */
 	gap_start = mm->highest_vm_end;
+	gap_start += gap_start_offset(info, gap_start);
 	gap_end = ULONG_MAX;  /* Only for VM_BUG_ON below */
 	if (gap_start > high_limit)
 		return -ENOMEM;
 
 found:
 	/* We found a suitable gap. Clip it with the original low_limit. */
-	if (gap_start < info->low_limit)
+	if (gap_start < info->low_limit) {
 		gap_start = info->low_limit;
-
-	/* Adjust gap address to the desired alignment */
-	gap_start += (info->align_offset - gap_start) & info->align_mask;
+		gap_start += gap_start_offset(info, gap_start);
+	}
 
 	VM_BUG_ON(gap_start + info->length > info->high_limit);
 	VM_BUG_ON(gap_start + info->length > gap_end);
@@ -1993,16 +1983,14 @@ unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info)
 	struct vm_area_struct *vma;
 	unsigned long length, low_limit, high_limit, gap_start, gap_end;
 
-	/* Adjust search length to account for worst case alignment overhead */
-	length = info->length + info->align_mask;
-	if (length < info->length)
-		return -ENOMEM;
+	length = info->length;
 
 	/*
 	 * Adjust search limits by the desired length.
 	 * See implementation comment at top of unmapped_area().
 	 */
 	gap_end = info->high_limit;
+	gap_end -= gap_end_offset(info, gap_end);
 	if (gap_end < length)
 		return -ENOMEM;
 	high_limit = gap_end - length;
@@ -2039,6 +2027,7 @@ unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info)
 check_current:
 		/* Check if current node has a suitable gap */
 		gap_end = vm_start_gap(vma);
+		gap_end -= gap_end_offset(info, gap_end);
 		if (gap_end < low_limit)
 			return -ENOMEM;
 		if (gap_start <= high_limit &&
@@ -2073,13 +2062,14 @@ check_current:
 
 found:
 	/* We found a suitable gap. Clip it with the original high_limit. */
-	if (gap_end > info->high_limit)
+	if (gap_end > info->high_limit) {
 		gap_end = info->high_limit;
+		gap_end -= gap_end_offset(info, gap_end);
+	}
 
 found_highest:
 	/* Compute highest gap address at the desired alignment */
 	gap_end -= info->length;
-	gap_end -= (gap_end - info->align_offset) & info->align_mask;
 
 	VM_BUG_ON(gap_end < info->low_limit);
 	VM_BUG_ON(gap_end < gap_start);
@@ -3006,15 +2996,16 @@ static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long fla
 	struct rb_node **rb_link, *rb_parent;
 	pgoff_t pgoff = addr >> PAGE_SHIFT;
 	int error;
+	unsigned long mapped_addr;
 
 	/* Until we need other flags, refuse anything except VM_EXEC. */
 	if ((flags & (~VM_EXEC)) != 0)
 		return -EINVAL;
 	flags |= VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
 
-	error = get_unmapped_area(NULL, addr, len, 0, MAP_FIXED);
-	if (offset_in_page(error))
-		return error;
+	mapped_addr = get_unmapped_area(NULL, addr, len, 0, MAP_FIXED);
+	if (IS_ERR_VALUE(mapped_addr))
+		return mapped_addr;
 
 	error = mlock_future_check(mm, mm->def_flags, len);
 	if (error)
diff --git a/mm/mremap.c b/mm/mremap.c
index 1fc8a29fbe3f..122938dcec15 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -558,7 +558,7 @@ static unsigned long mremap_to(unsigned long addr, unsigned long old_len,
 	ret = get_unmapped_area(vma->vm_file, new_addr, new_len, vma->vm_pgoff +
 				((addr - vma->vm_start) >> PAGE_SHIFT),
 				map_flags);
-	if (offset_in_page(ret))
+	if (IS_ERR_VALUE(ret))
 		goto out1;
 
 	ret = move_vma(vma, addr, old_len, new_len, new_addr, locked, uf,
@@ -706,7 +706,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
 					vma->vm_pgoff +
 					((addr - vma->vm_start) >> PAGE_SHIFT),
 					map_flags);
-		if (offset_in_page(new_addr)) {
+		if (IS_ERR_VALUE(new_addr)) {
 			ret = new_addr;
 			goto out;
 		}
diff --git a/mm/nommu.c b/mm/nommu.c
index 99b7ec318824..21ddf689d4fa 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -637,7 +637,7 @@ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma)
 	if (rb_prev)
 		prev = rb_entry(rb_prev, struct vm_area_struct, vm_rb);
 
-	__vma_link_list(mm, vma, prev, parent);
+	__vma_link_list(mm, vma, prev);
 }
 
 /*
@@ -673,13 +673,7 @@ static void delete_vma_from_mm(struct vm_area_struct *vma)
 	/* remove from the MM's tree and list */
 	rb_erase(&vma->vm_rb, &mm->mm_rb);
 
-	if (vma->vm_prev)
-		vma->vm_prev->vm_next = vma->vm_next;
-	else
-		mm->mmap = vma->vm_next;
-
-	if (vma->vm_next)
-		vma->vm_next->vm_prev = vma->vm_prev;
+	__vma_unlink_list(mm, vma);
 }
 
 /*
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 71e3acea7817..314ce1a3cf25 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -377,36 +377,13 @@ static void select_bad_process(struct oom_control *oc)
 	}
 }
 
-static int dump_task(struct task_struct *p, void *arg)
-{
-	struct oom_control *oc = arg;
-	struct task_struct *task;
-
-	if (oom_unkillable_task(p))
-		return 0;
-
-	/* p may not have freeable memory in nodemask */
-	if (!is_memcg_oom(oc) && !oom_cpuset_eligible(p, oc))
-		return 0;
 
-	task = find_lock_task_mm(p);
-	if (!task) {
-		/*
-		 * This is a kthread or all of p's threads have already
-		 * detached their mm's.  There's no need to report
-		 * them; they can't be oom killed anyway.
-		 */
-		return 0;
+static int add_candidate_task(struct task_struct *p, void *arg)
+{
+	if (!oom_unkillable_task(p)) {
+		get_task_struct(p);
+		list_add_tail(&p->oom_victim_list, (struct list_head *) arg);
 	}
-
-	pr_info("[%7d] %5d %5d %8lu %8lu %8ld %8lu         %5hd %s\n",
-		task->pid, from_kuid(&init_user_ns, task_uid(task)),
-		task->tgid, task->mm->total_vm, get_mm_rss(task->mm),
-		mm_pgtables_bytes(task->mm),
-		get_mm_counter(task->mm, MM_SWAPENTS),
-		task->signal->oom_score_adj, task->comm);
-	task_unlock(task);
-
 	return 0;
 }
 
@@ -422,19 +399,41 @@ static int dump_task(struct task_struct *p, void *arg)
  */
 static void dump_tasks(struct oom_control *oc)
 {
-	pr_info("Tasks state (memory values in pages):\n");
-	pr_info("[  pid  ]   uid  tgid total_vm      rss pgtables_bytes swapents oom_score_adj name\n");
+	LIST_HEAD(list);
+	struct task_struct *p;
+	struct task_struct *t;
 
 	if (is_memcg_oom(oc))
-		mem_cgroup_scan_tasks(oc->memcg, dump_task, oc);
+		mem_cgroup_scan_tasks(oc->memcg, add_candidate_task, &list);
 	else {
-		struct task_struct *p;
-
 		rcu_read_lock();
 		for_each_process(p)
-			dump_task(p, oc);
+			add_candidate_task(p, &list);
 		rcu_read_unlock();
 	}
+	pr_info("Tasks state (memory values in pages):\n");
+	pr_info("[  pid  ]   uid  tgid total_vm      rss pgtables_bytes swapents oom_score_adj name\n");
+	list_for_each_entry(p, &list, oom_victim_list) {
+		cond_resched();
+		/* p may not have freeable memory in nodemask */
+		if (!is_memcg_oom(oc) && !oom_cpuset_eligible(p, oc))
+			continue;
+		/* All of p's threads might have already detached their mm's. */
+		t = find_lock_task_mm(p);
+		if (!t)
+			continue;
+		pr_info("[%7d] %5d %5d %8lu %8lu %8ld %8lu         %5hd %s\n",
+			t->pid, from_kuid(&init_user_ns, task_uid(t)),
+			t->tgid, t->mm->total_vm, get_mm_rss(t->mm),
+			mm_pgtables_bytes(t->mm),
+			get_mm_counter(t->mm, MM_SWAPENTS),
+			t->signal->oom_score_adj, t->comm);
+		task_unlock(t);
+	}
+	list_for_each_entry_safe(p, t, &list, oom_victim_list) {
+		list_del(&p->oom_victim_list);
+		put_task_struct(p);
+	}
 }
 
 static void dump_oom_summary(struct oom_control *oc, struct task_struct *victim)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index ecc3dbad606b..12f3ce09d33d 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1948,6 +1948,14 @@ void __init page_alloc_init_late(void)
 	wait_for_completion(&pgdat_init_all_done_comp);
 
 	/*
+	 * The number of managed pages has changed due to the initialisation
+	 * so the pcpu batch and high limits needs to be updated or the limits
+	 * will be artificially small.
+	 */
+	for_each_populated_zone(zone)
+		zone_pcp_update(zone);
+
+	/*
 	 * We initialized the rest of the deferred pages.  Permanently disable
 	 * on-demand struct page initialization.
 	 */
@@ -5944,10 +5952,10 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
 #ifdef CONFIG_ZONE_DEVICE
 void __ref memmap_init_zone_device(struct zone *zone,
 				   unsigned long start_pfn,
-				   unsigned long size,
+				   unsigned long nr_pages,
 				   struct dev_pagemap *pgmap)
 {
-	unsigned long pfn, end_pfn = start_pfn + size;
+	unsigned long pfn, end_pfn = start_pfn + nr_pages;
 	struct pglist_data *pgdat = zone->zone_pgdat;
 	struct vmem_altmap *altmap = pgmap_altmap(pgmap);
 	unsigned long zone_idx = zone_idx(zone);
@@ -5964,7 +5972,7 @@ void __ref memmap_init_zone_device(struct zone *zone,
 	 */
 	if (altmap) {
 		start_pfn = altmap->base_pfn + vmem_altmap_offset(altmap);
-		size = end_pfn - start_pfn;
+		nr_pages = end_pfn - start_pfn;
 	}
 
 	for (pfn = start_pfn; pfn < end_pfn; pfn++) {
@@ -6011,7 +6019,7 @@ void __ref memmap_init_zone_device(struct zone *zone,
 	}
 
 	pr_info("%s initialised %lu pages in %ums\n", __func__,
-		size, jiffies_to_msecs(jiffies - start));
+		nr_pages, jiffies_to_msecs(jiffies - start));
 }
 
 #endif
@@ -7985,6 +7993,15 @@ int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *table, int write,
 	return 0;
 }
 
+static void __zone_pcp_update(struct zone *zone)
+{
+	unsigned int cpu;
+
+	for_each_possible_cpu(cpu)
+		pageset_set_high_and_batch(zone,
+				per_cpu_ptr(zone->pageset, cpu));
+}
+
 /*
  * percpu_pagelist_fraction - changes the pcp->high for each zone on each
  * cpu.  It is the fraction of total pages in each zone that a hot per cpu
@@ -8016,13 +8033,8 @@ int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *table, int write,
 	if (percpu_pagelist_fraction == old_percpu_pagelist_fraction)
 		goto out;
 
-	for_each_populated_zone(zone) {
-		unsigned int cpu;
-
-		for_each_possible_cpu(cpu)
-			pageset_set_high_and_batch(zone,
-					per_cpu_ptr(zone->pageset, cpu));
-	}
+	for_each_populated_zone(zone)
+		__zone_pcp_update(zone);
 out:
 	mutex_unlock(&pcp_batch_high_lock);
 	return ret;
@@ -8258,7 +8270,7 @@ bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
 		 * The HWPoisoned page may be not in buddy system, and
 		 * page_count() is not 0.
 		 */
-		if ((flags & SKIP_HWPOISON) && PageHWPoison(page))
+		if ((flags & MEMORY_OFFLINE) && PageHWPoison(page))
 			continue;
 
 		if (__PageMovable(page))
@@ -8474,7 +8486,7 @@ int alloc_contig_range(unsigned long start, unsigned long end,
 	}
 
 	/* Make sure the range is really isolated. */
-	if (test_pages_isolated(outer_start, end, false)) {
+	if (test_pages_isolated(outer_start, end, 0)) {
 		pr_info_ratelimited("%s: [%lx, %lx) PFNs busy\n",
 			__func__, outer_start, end);
 		ret = -EBUSY;
@@ -8499,6 +8511,107 @@ done:
 				pfn_max_align_up(end), migratetype);
 	return ret;
 }
+
+static int __alloc_contig_pages(unsigned long start_pfn,
+				unsigned long nr_pages, gfp_t gfp_mask)
+{
+	unsigned long end_pfn = start_pfn + nr_pages;
+
+	return alloc_contig_range(start_pfn, end_pfn, MIGRATE_MOVABLE,
+				  gfp_mask);
+}
+
+static bool pfn_range_valid_contig(struct zone *z, unsigned long start_pfn,
+				   unsigned long nr_pages)
+{
+	unsigned long i, end_pfn = start_pfn + nr_pages;
+	struct page *page;
+
+	for (i = start_pfn; i < end_pfn; i++) {
+		page = pfn_to_online_page(i);
+		if (!page)
+			return false;
+
+		if (page_zone(page) != z)
+			return false;
+
+		if (PageReserved(page))
+			return false;
+
+		if (page_count(page) > 0)
+			return false;
+
+		if (PageHuge(page))
+			return false;
+	}
+	return true;
+}
+
+static bool zone_spans_last_pfn(const struct zone *zone,
+				unsigned long start_pfn, unsigned long nr_pages)
+{
+	unsigned long last_pfn = start_pfn + nr_pages - 1;
+
+	return zone_spans_pfn(zone, last_pfn);
+}
+
+/**
+ * alloc_contig_pages() -- tries to find and allocate contiguous range of pages
+ * @nr_pages:	Number of contiguous pages to allocate
+ * @gfp_mask:	GFP mask to limit search and used during compaction
+ * @nid:	Target node
+ * @nodemask:	Mask for other possible nodes
+ *
+ * This routine is a wrapper around alloc_contig_range(). It scans over zones
+ * on an applicable zonelist to find a contiguous pfn range which can then be
+ * tried for allocation with alloc_contig_range(). This routine is intended
+ * for allocation requests which can not be fulfilled with the buddy allocator.
+ *
+ * The allocated memory is always aligned to a page boundary. If nr_pages is a
+ * power of two then the alignment is guaranteed to be to the given nr_pages
+ * (e.g. 1GB request would be aligned to 1GB).
+ *
+ * Allocated pages can be freed with free_contig_range() or by manually calling
+ * __free_page() on each allocated page.
+ *
+ * Return: pointer to contiguous pages on success, or NULL if not successful.
+ */
+struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask,
+				int nid, nodemask_t *nodemask)
+{
+	unsigned long ret, pfn, flags;
+	struct zonelist *zonelist;
+	struct zone *zone;
+	struct zoneref *z;
+
+	zonelist = node_zonelist(nid, gfp_mask);
+	for_each_zone_zonelist_nodemask(zone, z, zonelist,
+					gfp_zone(gfp_mask), nodemask) {
+		spin_lock_irqsave(&zone->lock, flags);
+
+		pfn = ALIGN(zone->zone_start_pfn, nr_pages);
+		while (zone_spans_last_pfn(zone, pfn, nr_pages)) {
+			if (pfn_range_valid_contig(zone, pfn, nr_pages)) {
+				/*
+				 * We release the zone lock here because
+				 * alloc_contig_range() will also lock the zone
+				 * at some point. If there's an allocation
+				 * spinning on this lock, it may win the race
+				 * and cause alloc_contig_range() to fail...
+				 */
+				spin_unlock_irqrestore(&zone->lock, flags);
+				ret = __alloc_contig_pages(pfn, nr_pages,
+							gfp_mask);
+				if (!ret)
+					return pfn_to_page(pfn);
+				spin_lock_irqsave(&zone->lock, flags);
+			}
+			pfn += nr_pages;
+		}
+		spin_unlock_irqrestore(&zone->lock, flags);
+	}
+	return NULL;
+}
 #endif /* CONFIG_CONTIG_ALLOC */
 
 void free_contig_range(unsigned long pfn, unsigned int nr_pages)
@@ -8514,21 +8627,16 @@ void free_contig_range(unsigned long pfn, unsigned int nr_pages)
 	WARN(count != 0, "%d pages are still in use!\n", count);
 }
 
-#ifdef CONFIG_MEMORY_HOTPLUG
 /*
  * The zone indicated has a new number of managed_pages; batch sizes and percpu
  * page high values need to be recalulated.
  */
 void __meminit zone_pcp_update(struct zone *zone)
 {
-	unsigned cpu;
 	mutex_lock(&pcp_batch_high_lock);
-	for_each_possible_cpu(cpu)
-		pageset_set_high_and_batch(zone,
-				per_cpu_ptr(zone->pageset, cpu));
+	__zone_pcp_update(zone);
 	mutex_unlock(&pcp_batch_high_lock);
 }
-#endif
 
 void zone_pcp_reset(struct zone *zone)
 {
@@ -8559,7 +8667,7 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
 {
 	struct page *page;
 	struct zone *zone;
-	unsigned int order, i;
+	unsigned int order;
 	unsigned long pfn;
 	unsigned long flags;
 	unsigned long offlined_pages = 0;
@@ -8587,7 +8695,6 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
 		 */
 		if (unlikely(!PageBuddy(page) && PageHWPoison(page))) {
 			pfn++;
-			SetPageReserved(page);
 			offlined_pages++;
 			continue;
 		}
@@ -8601,8 +8708,6 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
 			pfn, 1 << order, end_pfn);
 #endif
 		del_page_from_free_area(page, &zone->free_area[order]);
-		for (i = 0; i < (1 << order); i++)
-			SetPageReserved((page+i));
 		pfn += (1 << order);
 	}
 	spin_unlock_irqrestore(&zone->lock, flags);
diff --git a/mm/page_io.c b/mm/page_io.c
index 24ee600f9131..83db25aee6f1 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -22,6 +22,7 @@
 #include <linux/writeback.h>
 #include <linux/frontswap.h>
 #include <linux/blkdev.h>
+#include <linux/psi.h>
 #include <linux/uio.h>
 #include <linux/sched/task.h>
 #include <asm/pgtable.h>
@@ -354,10 +355,19 @@ int swap_readpage(struct page *page, bool synchronous)
 	struct swap_info_struct *sis = page_swap_info(page);
 	blk_qc_t qc;
 	struct gendisk *disk;
+	unsigned long pflags;
 
 	VM_BUG_ON_PAGE(!PageSwapCache(page) && !synchronous, page);
 	VM_BUG_ON_PAGE(!PageLocked(page), page);
 	VM_BUG_ON_PAGE(PageUptodate(page), page);
+
+	/*
+	 * Count submission time as memory stall. When the device is congested,
+	 * or the submitting cgroup IO-throttled, submission can be a
+	 * significant part of overall IO time.
+	 */
+	psi_memstall_enter(&pflags);
+
 	if (frontswap_load(page) == 0) {
 		SetPageUptodate(page);
 		unlock_page(page);
@@ -371,7 +381,7 @@ int swap_readpage(struct page *page, bool synchronous)
 		ret = mapping->a_ops->readpage(swap_file, page);
 		if (!ret)
 			count_vm_event(PSWPIN);
-		return ret;
+		goto out;
 	}
 
 	ret = bdev_read_page(sis->bdev, swap_page_sector(page), page);
@@ -382,7 +392,7 @@ int swap_readpage(struct page *page, bool synchronous)
 		}
 
 		count_vm_event(PSWPIN);
-		return 0;
+		goto out;
 	}
 
 	ret = 0;
@@ -418,6 +428,7 @@ int swap_readpage(struct page *page, bool synchronous)
 	bio_put(bio);
 
 out:
+	psi_memstall_leave(&pflags);
 	return ret;
 }
 
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 89c19c0feadb..04ee1663cdbe 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -168,7 +168,8 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages)
  * @migratetype:	Migrate type to set in error recovery.
  * @flags:		The following flags are allowed (they can be combined in
  *			a bit mask)
- *			SKIP_HWPOISON - ignore hwpoison pages
+ *			MEMORY_OFFLINE - isolate to offline (!allocate) memory
+ *					 e.g., skip over PageHWPoison() pages
  *			REPORT_FAILURE - report details about the failure to
  *			isolate the range
  *
@@ -257,7 +258,7 @@ void undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
  */
 static unsigned long
 __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
-				  bool skip_hwpoisoned_pages)
+				  int flags)
 {
 	struct page *page;
 
@@ -274,7 +275,7 @@ __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
 			 * simple way to verify that as VM_BUG_ON(), though.
 			 */
 			pfn += 1 << page_order(page);
-		else if (skip_hwpoisoned_pages && PageHWPoison(page))
+		else if ((flags & MEMORY_OFFLINE) && PageHWPoison(page))
 			/* A HWPoisoned page cannot be also PageBuddy */
 			pfn++;
 		else
@@ -286,7 +287,7 @@ __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
 
 /* Caller should ensure that requested range is in a single zone */
 int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
-			bool skip_hwpoisoned_pages)
+			int isol_flags)
 {
 	unsigned long pfn, flags;
 	struct page *page;
@@ -308,8 +309,7 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
 	/* Check all pages are free or marked as ISOLATED */
 	zone = page_zone(page);
 	spin_lock_irqsave(&zone->lock, flags);
-	pfn = __test_page_isolated_in_pageblock(start_pfn, end_pfn,
-						skip_hwpoisoned_pages);
+	pfn = __test_page_isolated_in_pageblock(start_pfn, end_pfn, isol_flags);
 	spin_unlock_irqrestore(&zone->lock, flags);
 
 	trace_test_pages_isolated(start_pfn, end_pfn, pfn);
diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
index 532c29276fce..3d7c01e76efc 100644
--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -24,18 +24,27 @@ void pgd_clear_bad(pgd_t *pgd)
 	pgd_clear(pgd);
 }
 
+#ifndef __PAGETABLE_P4D_FOLDED
 void p4d_clear_bad(p4d_t *p4d)
 {
 	p4d_ERROR(*p4d);
 	p4d_clear(p4d);
 }
+#endif
 
+#ifndef __PAGETABLE_PUD_FOLDED
 void pud_clear_bad(pud_t *pud)
 {
 	pud_ERROR(*pud);
 	pud_clear(pud);
 }
+#endif
 
+/*
+ * Note that the pmd variant below can't be stub'ed out just as for p4d/pud
+ * above. pmd folding is special and typically pmd_* macros refer to upper
+ * level even when folded
+ */
 void pmd_clear_bad(pmd_t *pmd)
 {
 	pmd_ERROR(*pmd);
diff --git a/mm/rmap.c b/mm/rmap.c
index 0c7b2a9400d4..2487c9dd9649 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -251,18 +251,37 @@ static inline void unlock_anon_vma_root(struct anon_vma *root)
  * Attach the anon_vmas from src to dst.
  * Returns 0 on success, -ENOMEM on failure.
  *
- * If dst->anon_vma is NULL this function tries to find and reuse existing
- * anon_vma which has no vmas and only one child anon_vma. This prevents
- * degradation of anon_vma hierarchy to endless linear chain in case of
- * constantly forking task. On the other hand, an anon_vma with more than one
- * child isn't reused even if there was no alive vma, thus rmap walker has a
- * good chance of avoiding scanning the whole hierarchy when it searches where
- * page is mapped.
+ * anon_vma_clone() is called by __vma_split(), __split_vma(), copy_vma() and
+ * anon_vma_fork(). The first three want an exact copy of src, while the last
+ * one, anon_vma_fork(), may try to reuse an existing anon_vma to prevent
+ * endless growth of anon_vma. Since dst->anon_vma is set to NULL before call,
+ * we can identify this case by checking (!dst->anon_vma && src->anon_vma).
+ *
+ * If (!dst->anon_vma && src->anon_vma) is true, this function tries to find
+ * and reuse existing anon_vma which has no vmas and only one child anon_vma.
+ * This prevents degradation of anon_vma hierarchy to endless linear chain in
+ * case of constantly forking task. On the other hand, an anon_vma with more
+ * than one child isn't reused even if there was no alive vma, thus rmap
+ * walker has a good chance of avoiding scanning the whole hierarchy when it
+ * searches where page is mapped.
  */
 int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src)
 {
 	struct anon_vma_chain *avc, *pavc;
 	struct anon_vma *root = NULL;
+	struct vm_area_struct *prev = dst->vm_prev, *pprev = src->vm_prev;
+
+	/*
+	 * If parent share anon_vma with its vm_prev, keep this sharing in in
+	 * child.
+	 *
+	 * 1. Parent has vm_prev, which implies we have vm_prev.
+	 * 2. Parent and its vm_prev have the same anon_vma.
+	 */
+	if (!dst->anon_vma && src->anon_vma &&
+	    pprev && pprev->anon_vma == src->anon_vma)
+		dst->anon_vma = prev->anon_vma;
+
 
 	list_for_each_entry_reverse(pavc, &src->anon_vma_chain, same_vma) {
 		struct anon_vma *anon_vma;
@@ -287,8 +306,8 @@ int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src)
 		 * will always reuse it. Root anon_vma is never reused:
 		 * it has self-parent reference and at least one child.
 		 */
-		if (!dst->anon_vma && anon_vma != src->anon_vma &&
-				anon_vma->degree < 2)
+		if (!dst->anon_vma && src->anon_vma &&
+		    anon_vma != src->anon_vma && anon_vma->degree < 2)
 			dst->anon_vma = anon_vma;
 	}
 	if (dst->anon_vma)
@@ -458,9 +477,10 @@ void __init anon_vma_init(void)
  * chain and verify that the page in question is indeed mapped in it
  * [ something equivalent to page_mapped_in_vma() ].
  *
- * Since anon_vma's slab is DESTROY_BY_RCU and we know from page_remove_rmap()
- * that the anon_vma pointer from page->mapping is valid if there is a
- * mapcount, we can dereference the anon_vma after observing those.
+ * Since anon_vma's slab is SLAB_TYPESAFE_BY_RCU and we know from
+ * page_remove_rmap() that the anon_vma pointer from page->mapping is valid
+ * if there is a mapcount, we can dereference the anon_vma after observing
+ * those.
  */
 struct anon_vma *page_get_anon_vma(struct page *page)
 {
@@ -1273,12 +1293,20 @@ static void page_remove_anon_compound_rmap(struct page *page)
 	if (TestClearPageDoubleMap(page)) {
 		/*
 		 * Subpages can be mapped with PTEs too. Check how many of
-		 * themi are still mapped.
+		 * them are still mapped.
 		 */
 		for (i = 0, nr = 0; i < HPAGE_PMD_NR; i++) {
 			if (atomic_add_negative(-1, &page[i]._mapcount))
 				nr++;
 		}
+
+		/*
+		 * Queue the page for deferred split if at least one small
+		 * page of the compound page is unmapped, but at least one
+		 * small page is still mapped.
+		 */
+		if (nr && nr < HPAGE_PMD_NR)
+			deferred_split_huge_page(page);
 	} else {
 		nr = HPAGE_PMD_NR;
 	}
@@ -1286,10 +1314,8 @@ static void page_remove_anon_compound_rmap(struct page *page)
 	if (unlikely(PageMlocked(page)))
 		clear_page_mlock(page);
 
-	if (nr) {
+	if (nr)
 		__mod_node_page_state(page_pgdat(page), NR_ANON_MAPPED, -nr);
-		deferred_split_huge_page(page);
-	}
 }
 
 /**
diff --git a/mm/shmem.c b/mm/shmem.c
index 220be9fa2c41..447fd575587c 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2022,16 +2022,14 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf)
 		    shmem_falloc->waitq &&
 		    vmf->pgoff >= shmem_falloc->start &&
 		    vmf->pgoff < shmem_falloc->next) {
+			struct file *fpin;
 			wait_queue_head_t *shmem_falloc_waitq;
 			DEFINE_WAIT_FUNC(shmem_fault_wait, synchronous_wake_function);
 
 			ret = VM_FAULT_NOPAGE;
-			if ((vmf->flags & FAULT_FLAG_ALLOW_RETRY) &&
-			   !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
-				/* It's polite to up mmap_sem if we can */
-				up_read(&vma->vm_mm->mmap_sem);
+			fpin = maybe_unlock_mmap_for_io(vmf, NULL);
+			if (fpin)
 				ret = VM_FAULT_RETRY;
-			}
 
 			shmem_falloc_waitq = shmem_falloc->waitq;
 			prepare_to_wait(shmem_falloc_waitq, &shmem_fault_wait,
@@ -2049,6 +2047,9 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf)
 			spin_lock(&inode->i_lock);
 			finish_wait(shmem_falloc_waitq, &shmem_fault_wait);
 			spin_unlock(&inode->i_lock);
+
+			if (fpin)
+				fput(fpin);
 			return ret;
 		}
 		spin_unlock(&inode->i_lock);
@@ -3928,7 +3929,7 @@ out2:
 static ssize_t shmem_enabled_show(struct kobject *kobj,
 		struct kobj_attribute *attr, char *buf)
 {
-	int values[] = {
+	static const int values[] = {
 		SHMEM_HUGE_ALWAYS,
 		SHMEM_HUGE_WITHIN_SIZE,
 		SHMEM_HUGE_ADVISE,
diff --git a/mm/slab.c b/mm/slab.c
index 66e5d8032bae..f1e1840af533 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1247,9 +1247,10 @@ void __init kmem_cache_init(void)
 	 * structures first.  Without this, further allocations will bug.
 	 */
 	kmalloc_caches[KMALLOC_NORMAL][INDEX_NODE] = create_kmalloc_cache(
-				kmalloc_info[INDEX_NODE].name,
-				kmalloc_size(INDEX_NODE), ARCH_KMALLOC_FLAGS,
-				0, kmalloc_size(INDEX_NODE));
+				kmalloc_info[INDEX_NODE].name[KMALLOC_NORMAL],
+				kmalloc_info[INDEX_NODE].size,
+				ARCH_KMALLOC_FLAGS, 0,
+				kmalloc_info[INDEX_NODE].size);
 	slab_state = PARTIAL_NODE;
 	setup_kmalloc_cache_index_table();
 
diff --git a/mm/slab.h b/mm/slab.h
index 68e455f2b698..3eb29ae75743 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -139,7 +139,7 @@ extern struct kmem_cache *kmem_cache;
 
 /* A table of kmalloc cache names and sizes */
 extern const struct kmalloc_info_struct {
-	const char *name;
+	const char *name[NR_KMALLOC_TYPES];
 	unsigned int size;
 } kmalloc_info[];
 
diff --git a/mm/slab_common.c b/mm/slab_common.c
index f9fb27b4c843..8afa188f6e20 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -1139,26 +1139,56 @@ struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags)
 	return kmalloc_caches[kmalloc_type(flags)][index];
 }
 
+#ifdef CONFIG_ZONE_DMA
+#define INIT_KMALLOC_INFO(__size, __short_size)			\
+{								\
+	.name[KMALLOC_NORMAL]  = "kmalloc-" #__short_size,	\
+	.name[KMALLOC_RECLAIM] = "kmalloc-rcl-" #__short_size,	\
+	.name[KMALLOC_DMA]     = "dma-kmalloc-" #__short_size,	\
+	.size = __size,						\
+}
+#else
+#define INIT_KMALLOC_INFO(__size, __short_size)			\
+{								\
+	.name[KMALLOC_NORMAL]  = "kmalloc-" #__short_size,	\
+	.name[KMALLOC_RECLAIM] = "kmalloc-rcl-" #__short_size,	\
+	.size = __size,						\
+}
+#endif
+
 /*
  * kmalloc_info[] is to make slub_debug=,kmalloc-xx option work at boot time.
  * kmalloc_index() supports up to 2^26=64MB, so the final entry of the table is
  * kmalloc-67108864.
  */
 const struct kmalloc_info_struct kmalloc_info[] __initconst = {
-	{NULL,                      0},		{"kmalloc-96",             96},
-	{"kmalloc-192",           192},		{"kmalloc-8",               8},
-	{"kmalloc-16",             16},		{"kmalloc-32",             32},
-	{"kmalloc-64",             64},		{"kmalloc-128",           128},
-	{"kmalloc-256",           256},		{"kmalloc-512",           512},
-	{"kmalloc-1k",           1024},		{"kmalloc-2k",           2048},
-	{"kmalloc-4k",           4096},		{"kmalloc-8k",           8192},
-	{"kmalloc-16k",         16384},		{"kmalloc-32k",         32768},
-	{"kmalloc-64k",         65536},		{"kmalloc-128k",       131072},
-	{"kmalloc-256k",       262144},		{"kmalloc-512k",       524288},
-	{"kmalloc-1M",        1048576},		{"kmalloc-2M",        2097152},
-	{"kmalloc-4M",        4194304},		{"kmalloc-8M",        8388608},
-	{"kmalloc-16M",      16777216},		{"kmalloc-32M",      33554432},
-	{"kmalloc-64M",      67108864}
+	INIT_KMALLOC_INFO(0, 0),
+	INIT_KMALLOC_INFO(96, 96),
+	INIT_KMALLOC_INFO(192, 192),
+	INIT_KMALLOC_INFO(8, 8),
+	INIT_KMALLOC_INFO(16, 16),
+	INIT_KMALLOC_INFO(32, 32),
+	INIT_KMALLOC_INFO(64, 64),
+	INIT_KMALLOC_INFO(128, 128),
+	INIT_KMALLOC_INFO(256, 256),
+	INIT_KMALLOC_INFO(512, 512),
+	INIT_KMALLOC_INFO(1024, 1k),
+	INIT_KMALLOC_INFO(2048, 2k),
+	INIT_KMALLOC_INFO(4096, 4k),
+	INIT_KMALLOC_INFO(8192, 8k),
+	INIT_KMALLOC_INFO(16384, 16k),
+	INIT_KMALLOC_INFO(32768, 32k),
+	INIT_KMALLOC_INFO(65536, 64k),
+	INIT_KMALLOC_INFO(131072, 128k),
+	INIT_KMALLOC_INFO(262144, 256k),
+	INIT_KMALLOC_INFO(524288, 512k),
+	INIT_KMALLOC_INFO(1048576, 1M),
+	INIT_KMALLOC_INFO(2097152, 2M),
+	INIT_KMALLOC_INFO(4194304, 4M),
+	INIT_KMALLOC_INFO(8388608, 8M),
+	INIT_KMALLOC_INFO(16777216, 16M),
+	INIT_KMALLOC_INFO(33554432, 32M),
+	INIT_KMALLOC_INFO(67108864, 64M)
 };
 
 /*
@@ -1208,36 +1238,14 @@ void __init setup_kmalloc_cache_index_table(void)
 	}
 }
 
-static const char *
-kmalloc_cache_name(const char *prefix, unsigned int size)
-{
-
-	static const char units[3] = "\0kM";
-	int idx = 0;
-
-	while (size >= 1024 && (size % 1024 == 0)) {
-		size /= 1024;
-		idx++;
-	}
-
-	return kasprintf(GFP_NOWAIT, "%s-%u%c", prefix, size, units[idx]);
-}
-
 static void __init
-new_kmalloc_cache(int idx, int type, slab_flags_t flags)
+new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags)
 {
-	const char *name;
-
-	if (type == KMALLOC_RECLAIM) {
+	if (type == KMALLOC_RECLAIM)
 		flags |= SLAB_RECLAIM_ACCOUNT;
-		name = kmalloc_cache_name("kmalloc-rcl",
-						kmalloc_info[idx].size);
-		BUG_ON(!name);
-	} else {
-		name = kmalloc_info[idx].name;
-	}
 
-	kmalloc_caches[type][idx] = create_kmalloc_cache(name,
+	kmalloc_caches[type][idx] = create_kmalloc_cache(
+					kmalloc_info[idx].name[type],
 					kmalloc_info[idx].size, flags, 0,
 					kmalloc_info[idx].size);
 }
@@ -1249,7 +1257,8 @@ new_kmalloc_cache(int idx, int type, slab_flags_t flags)
  */
 void __init create_kmalloc_caches(slab_flags_t flags)
 {
-	int i, type;
+	int i;
+	enum kmalloc_cache_type type;
 
 	for (type = KMALLOC_NORMAL; type <= KMALLOC_RECLAIM; type++) {
 		for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) {
@@ -1278,12 +1287,10 @@ void __init create_kmalloc_caches(slab_flags_t flags)
 		struct kmem_cache *s = kmalloc_caches[KMALLOC_NORMAL][i];
 
 		if (s) {
-			unsigned int size = kmalloc_size(i);
-			const char *n = kmalloc_cache_name("dma-kmalloc", size);
-
-			BUG_ON(!n);
 			kmalloc_caches[KMALLOC_DMA][i] = create_kmalloc_cache(
-				n, size, SLAB_CACHE_DMA | flags, 0, 0);
+				kmalloc_info[i].name[KMALLOC_DMA],
+				kmalloc_info[i].size,
+				SLAB_CACHE_DMA | flags, 0, 0);
 		}
 	}
 #endif
diff --git a/mm/slub.c b/mm/slub.c
index b25c807a111f..249e4c8be66a 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -93,9 +93,7 @@
  * minimal so we rely on the page allocators per cpu caches for
  * fast frees and allocs.
  *
- * Overloading of page flags that are otherwise used for LRU management.
- *
- * PageActive 		The slab is frozen and exempt from list processing.
+ * page->frozen		The slab is frozen and exempt from list processing.
  * 			This means that the slab is dedicated to a purpose
  * 			such as satisfying allocations for a specific
  * 			processor. Objects may be freed in the slab while
@@ -111,7 +109,7 @@
  * 			free objects in addition to the regular freelist
  * 			that requires the slab lock.
  *
- * PageError		Slab requires special handling due to debug
+ * SLAB_DEBUG_FLAGS	Slab requires special handling due to debug
  * 			options set. This moves	slab handling out of
  * 			the fast path and disables lockless freelists.
  */
@@ -736,6 +734,7 @@ static int check_bytes_and_report(struct kmem_cache *s, struct page *page,
 {
 	u8 *fault;
 	u8 *end;
+	u8 *addr = page_address(page);
 
 	metadata_access_enable();
 	fault = memchr_inv(start, value, bytes);
@@ -748,8 +747,9 @@ static int check_bytes_and_report(struct kmem_cache *s, struct page *page,
 		end--;
 
 	slab_bug(s, "%s overwritten", what);
-	pr_err("INFO: 0x%p-0x%p. First byte 0x%x instead of 0x%x\n",
-					fault, end - 1, fault[0], value);
+	pr_err("INFO: 0x%p-0x%p @offset=%tu. First byte 0x%x instead of 0x%x\n",
+					fault, end - 1, fault - addr,
+					fault[0], value);
 	print_trailer(s, page, object);
 
 	restore_bytes(s, what, value, fault, end);
@@ -844,7 +844,8 @@ static int slab_pad_check(struct kmem_cache *s, struct page *page)
 	while (end > fault && end[-1] == POISON_INUSE)
 		end--;
 
-	slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1);
+	slab_err(s, page, "Padding overwritten. 0x%p-0x%p @offset=%tu",
+			fault, end - 1, fault - start);
 	print_section(KERN_ERR, "Padding ", pad, remainder);
 
 	restore_bytes(s, "slab padding", POISON_INUSE, fault, end);
diff --git a/mm/sparse.c b/mm/sparse.c
index f6891c1992b1..a04c754ec99c 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -483,7 +483,7 @@ static void __init sparse_buffer_init(unsigned long size, int nid)
 	phys_addr_t addr = __pa(MAX_DMA_ADDRESS);
 	WARN_ON(sparsemap_buf);	/* forgot to call sparse_buffer_fini()? */
 	sparsemap_buf =
-		memblock_alloc_try_nid_raw(size, PAGE_SIZE,
+		memblock_alloc_exact_nid_raw(size, PAGE_SIZE,
 						addr,
 						MEMBLOCK_ALLOC_ACCESSIBLE, nid);
 	sparsemap_buf_end = sparsemap_buf + size;
diff --git a/mm/swap.c b/mm/swap.c
index 38c3fa4308e2..5341ae93861f 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -373,9 +373,16 @@ static void __lru_cache_activate_page(struct page *page)
 void mark_page_accessed(struct page *page)
 {
 	page = compound_head(page);
-	if (!PageActive(page) && !PageUnevictable(page) &&
-			PageReferenced(page)) {
 
+	if (!PageReferenced(page)) {
+		SetPageReferenced(page);
+	} else if (PageUnevictable(page)) {
+		/*
+		 * Unevictable pages are on the "LRU_UNEVICTABLE" list. But,
+		 * this list is never rotated or maintained, so marking an
+		 * evictable page accessed has no effect.
+		 */
+	} else if (!PageActive(page)) {
 		/*
 		 * If the page is on the LRU, queue it for activation via
 		 * activate_page_pvecs. Otherwise, assume the page is on a
@@ -389,8 +396,6 @@ void mark_page_accessed(struct page *page)
 		ClearPageReferenced(page);
 		if (page_is_file_cache(page))
 			workingset_activation(page);
-	} else if (!PageReferenced(page)) {
-		SetPageReferenced(page);
 	}
 	if (page_is_idle(page))
 		clear_page_idle(page);
@@ -708,9 +713,10 @@ static void lru_add_drain_per_cpu(struct work_struct *dummy)
  */
 void lru_add_drain_all(void)
 {
+	static seqcount_t seqcount = SEQCNT_ZERO(seqcount);
 	static DEFINE_MUTEX(lock);
 	static struct cpumask has_work;
-	int cpu;
+	int cpu, seq;
 
 	/*
 	 * Make sure nobody triggers this path before mm_percpu_wq is fully
@@ -719,7 +725,19 @@ void lru_add_drain_all(void)
 	if (WARN_ON(!mm_percpu_wq))
 		return;
 
+	seq = raw_read_seqcount_latch(&seqcount);
+
 	mutex_lock(&lock);
+
+	/*
+	 * Piggyback on drain started and finished while we waited for lock:
+	 * all pages pended at the time of our enter were drained from vectors.
+	 */
+	if (__read_seqcount_retry(&seqcount, seq))
+		goto done;
+
+	raw_write_seqcount_latch(&seqcount);
+
 	cpumask_clear(&has_work);
 
 	for_each_online_cpu(cpu) {
@@ -740,6 +758,7 @@ void lru_add_drain_all(void)
 	for_each_cpu(cpu, &has_work)
 		flush_work(&per_cpu(lru_add_drain_work, cpu));
 
+done:
 	mutex_unlock(&lock);
 }
 #else
diff --git a/mm/swapfile.c b/mm/swapfile.c
index dab43523afdd..bb3261d45b6a 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -2887,6 +2887,13 @@ static int claim_swapfile(struct swap_info_struct *p, struct inode *inode)
 		error = set_blocksize(p->bdev, PAGE_SIZE);
 		if (error < 0)
 			return error;
+		/*
+		 * Zoned block devices contain zones that have a sequential
+		 * write only restriction.  Hence zoned block devices are not
+		 * suitable for swapping.  Disallow them here.
+		 */
+		if (blk_queue_is_zoned(p->bdev->bd_queue))
+			return -EINVAL;
 		p->flags |= SWP_BLKDEV;
 	} else if (S_ISREG(inode->i_mode)) {
 		p->bdev = inode->i_sb->s_bdev;
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index c7ae74ce5ff3..1b0d7abad1d4 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -18,6 +18,36 @@
 #include <asm/tlbflush.h>
 #include "internal.h"
 
+static __always_inline
+struct vm_area_struct *find_dst_vma(struct mm_struct *dst_mm,
+				    unsigned long dst_start,
+				    unsigned long len)
+{
+	/*
+	 * Make sure that the dst range is both valid and fully within a
+	 * single existing vma.
+	 */
+	struct vm_area_struct *dst_vma;
+
+	dst_vma = find_vma(dst_mm, dst_start);
+	if (!dst_vma)
+		return NULL;
+
+	if (dst_start < dst_vma->vm_start ||
+	    dst_start + len > dst_vma->vm_end)
+		return NULL;
+
+	/*
+	 * Check the vma is registered in uffd, this is required to
+	 * enforce the VM_MAYWRITE check done at uffd registration
+	 * time.
+	 */
+	if (!dst_vma->vm_userfaultfd_ctx.ctx)
+		return NULL;
+
+	return dst_vma;
+}
+
 static int mcopy_atomic_pte(struct mm_struct *dst_mm,
 			    pmd_t *dst_pmd,
 			    struct vm_area_struct *dst_vma,
@@ -60,7 +90,7 @@ static int mcopy_atomic_pte(struct mm_struct *dst_mm,
 
 	/*
 	 * The memory barrier inside __SetPageUptodate makes sure that
-	 * preceeding stores to the page contents become visible before
+	 * preceding stores to the page contents become visible before
 	 * the set_pte_at() write.
 	 */
 	__SetPageUptodate(page);
@@ -184,7 +214,6 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
 	unsigned long src_addr, dst_addr;
 	long copied;
 	struct page *page;
-	struct hstate *h;
 	unsigned long vma_hpagesize;
 	pgoff_t idx;
 	u32 hash;
@@ -221,20 +250,9 @@ retry:
 	 */
 	if (!dst_vma) {
 		err = -ENOENT;
-		dst_vma = find_vma(dst_mm, dst_start);
+		dst_vma = find_dst_vma(dst_mm, dst_start, len);
 		if (!dst_vma || !is_vm_hugetlb_page(dst_vma))
 			goto out_unlock;
-		/*
-		 * Check the vma is registered in uffd, this is
-		 * required to enforce the VM_MAYWRITE check done at
-		 * uffd registration time.
-		 */
-		if (!dst_vma->vm_userfaultfd_ctx.ctx)
-			goto out_unlock;
-
-		if (dst_start < dst_vma->vm_start ||
-		    dst_start + len > dst_vma->vm_end)
-			goto out_unlock;
 
 		err = -EINVAL;
 		if (vma_hpagesize != vma_kernel_pagesize(dst_vma))
@@ -243,10 +261,6 @@ retry:
 		vm_shared = dst_vma->vm_flags & VM_SHARED;
 	}
 
-	if (WARN_ON(dst_addr & (vma_hpagesize - 1) ||
-		    (len - copied) & (vma_hpagesize - 1)))
-		goto out_unlock;
-
 	/*
 	 * If not shared, ensure the dst_vma has a anon_vma.
 	 */
@@ -256,24 +270,21 @@ retry:
 			goto out_unlock;
 	}
 
-	h = hstate_vma(dst_vma);
-
 	while (src_addr < src_start + len) {
 		pte_t dst_pteval;
 
 		BUG_ON(dst_addr >= dst_start + len);
-		VM_BUG_ON(dst_addr & ~huge_page_mask(h));
 
 		/*
 		 * Serialize via hugetlb_fault_mutex
 		 */
 		idx = linear_page_index(dst_vma, dst_addr);
 		mapping = dst_vma->vm_file->f_mapping;
-		hash = hugetlb_fault_mutex_hash(h, mapping, idx, dst_addr);
+		hash = hugetlb_fault_mutex_hash(mapping, idx);
 		mutex_lock(&hugetlb_fault_mutex_table[hash]);
 
 		err = -ENOMEM;
-		dst_pte = huge_pte_alloc(dst_mm, dst_addr, huge_page_size(h));
+		dst_pte = huge_pte_alloc(dst_mm, dst_addr, vma_hpagesize);
 		if (!dst_pte) {
 			mutex_unlock(&hugetlb_fault_mutex_table[hash]);
 			goto out_unlock;
@@ -300,7 +311,8 @@ retry:
 
 			err = copy_huge_page_from_user(page,
 						(const void __user *)src_addr,
-						pages_per_huge_page(h), true);
+						vma_hpagesize / PAGE_SIZE,
+						true);
 			if (unlikely(err)) {
 				err = -EFAULT;
 				goto out;
@@ -475,20 +487,9 @@ retry:
 	 * both valid and fully within a single existing vma.
 	 */
 	err = -ENOENT;
-	dst_vma = find_vma(dst_mm, dst_start);
+	dst_vma = find_dst_vma(dst_mm, dst_start, len);
 	if (!dst_vma)
 		goto out_unlock;
-	/*
-	 * Check the vma is registered in uffd, this is required to
-	 * enforce the VM_MAYWRITE check done at uffd registration
-	 * time.
-	 */
-	if (!dst_vma->vm_userfaultfd_ctx.ctx)
-		goto out_unlock;
-
-	if (dst_start < dst_vma->vm_start ||
-	    dst_start + len > dst_vma->vm_end)
-		goto out_unlock;
 
 	err = -EINVAL;
 	/*
diff --git a/mm/util.c b/mm/util.c
index 3ad6db9a722e..988d11e6c17c 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -271,7 +271,7 @@ void *memdup_user_nul(const void __user *src, size_t len)
 EXPORT_SYMBOL(memdup_user_nul);
 
 void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
-		struct vm_area_struct *prev, struct rb_node *rb_parent)
+		struct vm_area_struct *prev)
 {
 	struct vm_area_struct *next;
 
@@ -280,18 +280,28 @@ void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma,
 		next = prev->vm_next;
 		prev->vm_next = vma;
 	} else {
+		next = mm->mmap;
 		mm->mmap = vma;
-		if (rb_parent)
-			next = rb_entry(rb_parent,
-					struct vm_area_struct, vm_rb);
-		else
-			next = NULL;
 	}
 	vma->vm_next = next;
 	if (next)
 		next->vm_prev = vma;
 }
 
+void __vma_unlink_list(struct mm_struct *mm, struct vm_area_struct *vma)
+{
+	struct vm_area_struct *prev, *next;
+
+	next = vma->vm_next;
+	prev = vma->vm_prev;
+	if (prev)
+		prev->vm_next = next;
+	else
+		mm->mmap = next;
+	if (next)
+		next->vm_prev = prev;
+}
+
 /* Check if the vma is being used as a stack by this task */
 int vma_is_stack_for_current(struct vm_area_struct *vma)
 {
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index a3c70e275f4e..f48f64c8d200 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -331,6 +331,7 @@ EXPORT_SYMBOL(vmalloc_to_pfn);
 
 
 static DEFINE_SPINLOCK(vmap_area_lock);
+static DEFINE_SPINLOCK(free_vmap_area_lock);
 /* Export for kexec only */
 LIST_HEAD(vmap_area_list);
 static LLIST_HEAD(vmap_purge_list);
@@ -968,6 +969,19 @@ adjust_va_to_fit_type(struct vmap_area *va,
 			 * There are a few exceptions though, as an example it is
 			 * a first allocation (early boot up) when we have "one"
 			 * big free space that has to be split.
+			 *
+			 * Also we can hit this path in case of regular "vmap"
+			 * allocations, if "this" current CPU was not preloaded.
+			 * See the comment in alloc_vmap_area() why. If so, then
+			 * GFP_NOWAIT is used instead to get an extra object for
+			 * split purpose. That is rare and most time does not
+			 * occur.
+			 *
+			 * What happens if an allocation gets failed. Basically,
+			 * an "overflow" path is triggered to purge lazily freed
+			 * areas to free some memory, then, the "retry" path is
+			 * triggered to repeat one more time. See more details
+			 * in alloc_vmap_area() function.
 			 */
 			lva = kmem_cache_alloc(vmap_area_cachep, GFP_NOWAIT);
 			if (!lva)
@@ -1063,9 +1077,9 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
 		return ERR_PTR(-EBUSY);
 
 	might_sleep();
+	gfp_mask = gfp_mask & GFP_RECLAIM_MASK;
 
-	va = kmem_cache_alloc_node(vmap_area_cachep,
-			gfp_mask & GFP_RECLAIM_MASK, node);
+	va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
 	if (unlikely(!va))
 		return ERR_PTR(-ENOMEM);
 
@@ -1073,49 +1087,55 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
 	 * Only scan the relevant parts containing pointers to other objects
 	 * to avoid false negatives.
 	 */
-	kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask & GFP_RECLAIM_MASK);
+	kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
 
 retry:
 	/*
-	 * Preload this CPU with one extra vmap_area object to ensure
-	 * that we have it available when fit type of free area is
-	 * NE_FIT_TYPE.
+	 * Preload this CPU with one extra vmap_area object. It is used
+	 * when fit type of free area is NE_FIT_TYPE. Please note, it
+	 * does not guarantee that an allocation occurs on a CPU that
+	 * is preloaded, instead we minimize the case when it is not.
+	 * It can happen because of cpu migration, because there is a
+	 * race until the below spinlock is taken.
 	 *
 	 * The preload is done in non-atomic context, thus it allows us
 	 * to use more permissive allocation masks to be more stable under
-	 * low memory condition and high memory pressure.
+	 * low memory condition and high memory pressure. In rare case,
+	 * if not preloaded, GFP_NOWAIT is used.
 	 *
-	 * Even if it fails we do not really care about that. Just proceed
-	 * as it is. "overflow" path will refill the cache we allocate from.
+	 * Set "pva" to NULL here, because of "retry" path.
 	 */
-	preempt_disable();
-	if (!__this_cpu_read(ne_fit_preload_node)) {
-		preempt_enable();
-		pva = kmem_cache_alloc_node(vmap_area_cachep, GFP_KERNEL, node);
-		preempt_disable();
-
-		if (__this_cpu_cmpxchg(ne_fit_preload_node, NULL, pva)) {
-			if (pva)
-				kmem_cache_free(vmap_area_cachep, pva);
-		}
-	}
+	pva = NULL;
 
-	spin_lock(&vmap_area_lock);
-	preempt_enable();
+	if (!this_cpu_read(ne_fit_preload_node))
+		/*
+		 * Even if it fails we do not really care about that.
+		 * Just proceed as it is. If needed "overflow" path
+		 * will refill the cache we allocate from.
+		 */
+		pva = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
+
+	spin_lock(&free_vmap_area_lock);
+
+	if (pva && __this_cpu_cmpxchg(ne_fit_preload_node, NULL, pva))
+		kmem_cache_free(vmap_area_cachep, pva);
 
 	/*
 	 * If an allocation fails, the "vend" address is
 	 * returned. Therefore trigger the overflow path.
 	 */
 	addr = __alloc_vmap_area(size, align, vstart, vend);
+	spin_unlock(&free_vmap_area_lock);
+
 	if (unlikely(addr == vend))
 		goto overflow;
 
 	va->va_start = addr;
 	va->va_end = addr + size;
 	va->vm = NULL;
-	insert_vmap_area(va, &vmap_area_root, &vmap_area_list);
 
+	spin_lock(&vmap_area_lock);
+	insert_vmap_area(va, &vmap_area_root, &vmap_area_list);
 	spin_unlock(&vmap_area_lock);
 
 	BUG_ON(!IS_ALIGNED(va->va_start, align));
@@ -1125,7 +1145,6 @@ retry:
 	return va;
 
 overflow:
-	spin_unlock(&vmap_area_lock);
 	if (!purged) {
 		purge_vmap_area_lazy();
 		purged = 1;
@@ -1161,28 +1180,25 @@ int unregister_vmap_purge_notifier(struct notifier_block *nb)
 }
 EXPORT_SYMBOL_GPL(unregister_vmap_purge_notifier);
 
-static void __free_vmap_area(struct vmap_area *va)
+/*
+ * Free a region of KVA allocated by alloc_vmap_area
+ */
+static void free_vmap_area(struct vmap_area *va)
 {
 	/*
 	 * Remove from the busy tree/list.
 	 */
+	spin_lock(&vmap_area_lock);
 	unlink_va(va, &vmap_area_root);
+	spin_unlock(&vmap_area_lock);
 
 	/*
-	 * Merge VA with its neighbors, otherwise just add it.
+	 * Insert/Merge it back to the free tree/list.
 	 */
+	spin_lock(&free_vmap_area_lock);
 	merge_or_add_vmap_area(va,
 		&free_vmap_area_root, &free_vmap_area_list);
-}
-
-/*
- * Free a region of KVA allocated by alloc_vmap_area
- */
-static void free_vmap_area(struct vmap_area *va)
-{
-	spin_lock(&vmap_area_lock);
-	__free_vmap_area(va);
-	spin_unlock(&vmap_area_lock);
+	spin_unlock(&free_vmap_area_lock);
 }
 
 /*
@@ -1275,7 +1291,7 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end)
 	flush_tlb_kernel_range(start, end);
 	resched_threshold = lazy_max_pages() << 1;
 
-	spin_lock(&vmap_area_lock);
+	spin_lock(&free_vmap_area_lock);
 	llist_for_each_entry_safe(va, n_va, valist, purge_list) {
 		unsigned long nr = (va->va_end - va->va_start) >> PAGE_SHIFT;
 
@@ -1290,9 +1306,9 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end)
 		atomic_long_sub(nr, &vmap_lazy_nr);
 
 		if (atomic_long_read(&vmap_lazy_nr) < resched_threshold)
-			cond_resched_lock(&vmap_area_lock);
+			cond_resched_lock(&free_vmap_area_lock);
 	}
-	spin_unlock(&vmap_area_lock);
+	spin_unlock(&free_vmap_area_lock);
 	return true;
 }
 
@@ -2014,15 +2030,21 @@ int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page **pages)
 }
 EXPORT_SYMBOL_GPL(map_vm_area);
 
-static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va,
-			      unsigned long flags, const void *caller)
+static inline void setup_vmalloc_vm_locked(struct vm_struct *vm,
+	struct vmap_area *va, unsigned long flags, const void *caller)
 {
-	spin_lock(&vmap_area_lock);
 	vm->flags = flags;
 	vm->addr = (void *)va->va_start;
 	vm->size = va->va_end - va->va_start;
 	vm->caller = caller;
 	va->vm = vm;
+}
+
+static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va,
+			      unsigned long flags, const void *caller)
+{
+	spin_lock(&vmap_area_lock);
+	setup_vmalloc_vm_locked(vm, va, flags, caller);
 	spin_unlock(&vmap_area_lock);
 }
 
@@ -2440,7 +2462,7 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
 			goto fail;
 		}
 		area->pages[i] = page;
-		if (gfpflags_allow_blocking(gfp_mask|highmem_mask))
+		if (gfpflags_allow_blocking(gfp_mask))
 			cond_resched();
 	}
 	atomic_long_add(area->nr_pages, &nr_vmalloc_pages);
@@ -3262,7 +3284,7 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
 			goto err_free;
 	}
 retry:
-	spin_lock(&vmap_area_lock);
+	spin_lock(&free_vmap_area_lock);
 
 	/* start scanning - we scan from the top, begin with the last area */
 	area = term_area = last_area;
@@ -3344,29 +3366,38 @@ retry:
 		va = vas[area];
 		va->va_start = start;
 		va->va_end = start + size;
-
-		insert_vmap_area(va, &vmap_area_root, &vmap_area_list);
 	}
 
-	spin_unlock(&vmap_area_lock);
+	spin_unlock(&free_vmap_area_lock);
 
 	/* insert all vm's */
-	for (area = 0; area < nr_vms; area++)
-		setup_vmalloc_vm(vms[area], vas[area], VM_ALLOC,
+	spin_lock(&vmap_area_lock);
+	for (area = 0; area < nr_vms; area++) {
+		insert_vmap_area(vas[area], &vmap_area_root, &vmap_area_list);
+
+		setup_vmalloc_vm_locked(vms[area], vas[area], VM_ALLOC,
 				 pcpu_get_vm_areas);
+	}
+	spin_unlock(&vmap_area_lock);
 
 	kfree(vas);
 	return vms;
 
 recovery:
-	/* Remove previously inserted areas. */
+	/*
+	 * Remove previously allocated areas. There is no
+	 * need in removing these areas from the busy tree,
+	 * because they are inserted only on the final step
+	 * and when pcpu_get_vm_areas() is success.
+	 */
 	while (area--) {
-		__free_vmap_area(vas[area]);
+		merge_or_add_vmap_area(vas[area],
+			&free_vmap_area_root, &free_vmap_area_list);
 		vas[area] = NULL;
 	}
 
 overflow:
-	spin_unlock(&vmap_area_lock);
+	spin_unlock(&free_vmap_area_lock);
 	if (!purged) {
 		purge_vmap_area_lazy();
 		purged = true;
@@ -3417,9 +3448,12 @@ void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
 
 #ifdef CONFIG_PROC_FS
 static void *s_start(struct seq_file *m, loff_t *pos)
+	__acquires(&vmap_purge_lock)
 	__acquires(&vmap_area_lock)
 {
+	mutex_lock(&vmap_purge_lock);
 	spin_lock(&vmap_area_lock);
+
 	return seq_list_start(&vmap_area_list, *pos);
 }
 
@@ -3429,8 +3463,10 @@ static void *s_next(struct seq_file *m, void *p, loff_t *pos)
 }
 
 static void s_stop(struct seq_file *m, void *p)
+	__releases(&vmap_purge_lock)
 	__releases(&vmap_area_lock)
 {
+	mutex_unlock(&vmap_purge_lock);
 	spin_unlock(&vmap_area_lock);
 }
 
diff --git a/mm/vmscan.c b/mm/vmscan.c
index ee4eecc7e1c2..1154b3a2b637 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -775,7 +775,7 @@ static inline int is_page_cache_freeable(struct page *page)
 	return page_count(page) - page_has_private(page) == 1 + page_cache_pins;
 }
 
-static int may_write_to_inode(struct inode *inode, struct scan_control *sc)
+static int may_write_to_inode(struct inode *inode)
 {
 	if (current->flags & PF_SWAPWRITE)
 		return 1;
@@ -823,8 +823,7 @@ typedef enum {
  * pageout is called by shrink_page_list() for each dirty page.
  * Calls ->writepage().
  */
-static pageout_t pageout(struct page *page, struct address_space *mapping,
-			 struct scan_control *sc)
+static pageout_t pageout(struct page *page, struct address_space *mapping)
 {
 	/*
 	 * If the page is dirty, only perform writeback if that write
@@ -860,7 +859,7 @@ static pageout_t pageout(struct page *page, struct address_space *mapping,
 	}
 	if (mapping->a_ops->writepage == NULL)
 		return PAGE_ACTIVATE;
-	if (!may_write_to_inode(mapping->host, sc))
+	if (!may_write_to_inode(mapping->host))
 		return PAGE_KEEP;
 
 	if (clear_page_dirty_for_io(page)) {
@@ -1394,7 +1393,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 			 * starts and then write it out here.
 			 */
 			try_to_unmap_flush_dirty();
-			switch (pageout(page, mapping, sc)) {
+			switch (pageout(page, mapping)) {
 			case PAGE_KEEP:
 				goto keep_locked;
 			case PAGE_ACTIVATE:
@@ -2302,8 +2301,7 @@ enum scan_balance {
  * nr[2] = file inactive pages to scan; nr[3] = file active pages to scan
  */
 static void get_scan_count(struct lruvec *lruvec, struct mem_cgroup *memcg,
-			   struct scan_control *sc, unsigned long *nr,
-			   unsigned long *lru_pages)
+			   struct scan_control *sc, unsigned long *nr)
 {
 	int swappiness = mem_cgroup_swappiness(memcg);
 	struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat;
@@ -2454,7 +2452,6 @@ static void get_scan_count(struct lruvec *lruvec, struct mem_cgroup *memcg,
 	fraction[1] = fp;
 	denominator = ap + fp + 1;
 out:
-	*lru_pages = 0;
 	for_each_evictable_lru(lru) {
 		int file = is_file_lru(lru);
 		unsigned long lruvec_size;
@@ -2549,7 +2546,6 @@ out:
 			BUG();
 		}
 
-		*lru_pages += lruvec_size;
 		nr[lru] = scan;
 	}
 }
@@ -2558,7 +2554,7 @@ out:
  * This is a basic per-node page freer.  Used by both kswapd and direct reclaim.
  */
 static void shrink_node_memcg(struct pglist_data *pgdat, struct mem_cgroup *memcg,
-			      struct scan_control *sc, unsigned long *lru_pages)
+			      struct scan_control *sc)
 {
 	struct lruvec *lruvec = mem_cgroup_lruvec(pgdat, memcg);
 	unsigned long nr[NR_LRU_LISTS];
@@ -2570,7 +2566,7 @@ static void shrink_node_memcg(struct pglist_data *pgdat, struct mem_cgroup *memc
 	struct blk_plug plug;
 	bool scan_adjusted;
 
-	get_scan_count(lruvec, memcg, sc, nr, lru_pages);
+	get_scan_count(lruvec, memcg, sc, nr);
 
 	/* Record the original scan target for proportional adjustments later */
 	memcpy(targets, nr, sizeof(nr));
@@ -2758,7 +2754,6 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
 
 	do {
 		struct mem_cgroup *root = sc->target_mem_cgroup;
-		unsigned long node_lru_pages = 0;
 		struct mem_cgroup *memcg;
 
 		memset(&sc->nr, 0, sizeof(sc->nr));
@@ -2768,7 +2763,6 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
 
 		memcg = mem_cgroup_iter(root, NULL, NULL);
 		do {
-			unsigned long lru_pages;
 			unsigned long reclaimed;
 			unsigned long scanned;
 
@@ -2805,8 +2799,7 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
 
 			reclaimed = sc->nr_reclaimed;
 			scanned = sc->nr_scanned;
-			shrink_node_memcg(pgdat, memcg, sc, &lru_pages);
-			node_lru_pages += lru_pages;
+			shrink_node_memcg(pgdat, memcg, sc);
 
 			shrink_slab(sc->gfp_mask, pgdat->node_id, memcg,
 					sc->priority);
@@ -3317,15 +3310,16 @@ unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg,
 		.reclaim_idx = MAX_NR_ZONES - 1,
 		.may_swap = !noswap,
 	};
-	unsigned long lru_pages;
 
 	WARN_ON_ONCE(!current->reclaim_state);
 
 	sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
 			(GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK);
 
-	trace_mm_vmscan_memcg_softlimit_reclaim_begin(sc.order,
-						      sc.gfp_mask);
+	trace_mm_vmscan_memcg_softlimit_reclaim_begin(
+					cgroup_ino(memcg->css.cgroup),
+					sc.order,
+					sc.gfp_mask);
 
 	/*
 	 * NOTE: Although we can get the priority field, using it
@@ -3334,9 +3328,11 @@ unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg,
 	 * will pick up pages from other mem cgroup's as well. We hack
 	 * the priority and make it zero.
 	 */
-	shrink_node_memcg(pgdat, memcg, &sc, &lru_pages);
+	shrink_node_memcg(pgdat, memcg, &sc);
 
-	trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed);
+	trace_mm_vmscan_memcg_softlimit_reclaim_end(
+					cgroup_ino(memcg->css.cgroup),
+					sc.nr_reclaimed);
 
 	*nr_scanned = sc.nr_scanned;
 
@@ -3375,7 +3371,9 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
 
 	zonelist = &NODE_DATA(nid)->node_zonelists[ZONELIST_FALLBACK];
 
-	trace_mm_vmscan_memcg_reclaim_begin(0, sc.gfp_mask);
+	trace_mm_vmscan_memcg_reclaim_begin(
+				cgroup_ino(memcg->css.cgroup),
+				0, sc.gfp_mask);
 
 	psi_memstall_enter(&pflags);
 	noreclaim_flag = memalloc_noreclaim_save();
@@ -3385,7 +3383,9 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
 	memalloc_noreclaim_restore(noreclaim_flag);
 	psi_memstall_leave(&pflags);
 
-	trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed);
+	trace_mm_vmscan_memcg_reclaim_end(
+				cgroup_ino(memcg->css.cgroup),
+				nr_reclaimed);
 	set_task_reclaim_state(current, NULL);
 
 	return nr_reclaimed;
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 6afc892a148a..c37e07a73c30 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1084,7 +1084,8 @@ int fragmentation_index(struct zone *zone, unsigned int order)
 }
 #endif
 
-#if defined(CONFIG_PROC_FS) || defined(CONFIG_SYSFS) || defined(CONFIG_NUMA)
+#if defined(CONFIG_PROC_FS) || defined(CONFIG_SYSFS) || \
+    defined(CONFIG_NUMA) || defined(CONFIG_MEMCG)
 #ifdef CONFIG_ZONE_DMA
 #define TEXT_FOR_DMA(xx) xx "_dma",
 #else
@@ -1134,7 +1135,7 @@ const char * const vmstat_text[] = {
 	"numa_other",
 #endif
 
-	/* Node-based counters */
+	/* enum node_stat_item counters */
 	"nr_inactive_anon",
 	"nr_active_anon",
 	"nr_inactive_file",
@@ -1172,7 +1173,7 @@ const char * const vmstat_text[] = {
 	"nr_dirty_threshold",
 	"nr_dirty_background_threshold",
 
-#ifdef CONFIG_VM_EVENT_COUNTERS
+#if defined(CONFIG_VM_EVENT_COUNTERS) || defined(CONFIG_MEMCG)
 	/* enum vm_event_item counters */
 	"pgpgin",
 	"pgpgout",
@@ -1291,9 +1292,9 @@ const char * const vmstat_text[] = {
 	"swap_ra",
 	"swap_ra_hit",
 #endif
-#endif /* CONFIG_VM_EVENTS_COUNTERS */
+#endif /* CONFIG_VM_EVENT_COUNTERS || CONFIG_MEMCG */
 };
-#endif /* CONFIG_PROC_FS || CONFIG_SYSFS || CONFIG_NUMA */
+#endif /* CONFIG_PROC_FS || CONFIG_SYSFS || CONFIG_NUMA || CONFIG_MEMCG */
 
 #if (defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)) || \
      defined(CONFIG_PROC_FS)
@@ -1373,23 +1374,54 @@ static void pagetypeinfo_showfree_print(struct seq_file *m,
 					pg_data_t *pgdat, struct zone *zone)
 {
 	int order, mtype;
+	unsigned long nfree[MAX_ORDER][MIGRATE_TYPES];
 
-	for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
-		seq_printf(m, "Node %4d, zone %8s, type %12s ",
-					pgdat->node_id,
-					zone->name,
-					migratetype_names[mtype]);
-		for (order = 0; order < MAX_ORDER; ++order) {
+	lockdep_assert_held(&zone->lock);
+	lockdep_assert_irqs_disabled();
+
+	/*
+	 * MIGRATE_MOVABLE is usually the largest one in large memory
+	 * systems. We skip iterating that list. Instead, we compute it by
+	 * subtracting the total of the rests from free_area->nr_free.
+	 */
+	for (order = 0; order < MAX_ORDER; ++order) {
+		unsigned long nr_total = 0;
+		struct free_area *area = &(zone->free_area[order]);
+
+		for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
 			unsigned long freecount = 0;
-			struct free_area *area;
 			struct list_head *curr;
 
-			area = &(zone->free_area[order]);
-
+			if (mtype == MIGRATE_MOVABLE)
+				continue;
 			list_for_each(curr, &area->free_list[mtype])
 				freecount++;
-			seq_printf(m, "%6lu ", freecount);
+			nfree[order][mtype] = freecount;
+			nr_total += freecount;
+		}
+		nfree[order][MIGRATE_MOVABLE] = area->nr_free - nr_total;
+
+		/*
+		 * If we have already iterated more than 64k of list
+		 * entries, we might have hold the zone lock for too long.
+		 * Temporarily release the lock and reschedule before
+		 * continuing so that other lock waiters have a chance
+		 * to run.
+		 */
+		if (nr_total > (1 << 16)) {
+			spin_unlock_irq(&zone->lock);
+			cond_resched();
+			spin_lock_irq(&zone->lock);
 		}
+	}
+
+	for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
+		seq_printf(m, "Node %4d, zone %8s, type %12s ",
+					pgdat->node_id,
+					zone->name,
+					migratetype_names[mtype]);
+		for (order = 0; order < MAX_ORDER; ++order)
+			seq_printf(m, "%6lu ", nfree[order][mtype]);
 		seq_putc(m, '\n');
 	}
 }
@@ -1547,10 +1579,8 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
 	if (is_zone_first_populated(pgdat, zone)) {
 		seq_printf(m, "\n  per-node stats");
 		for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
-			seq_printf(m, "\n      %-12s %lu",
-				vmstat_text[i + NR_VM_ZONE_STAT_ITEMS +
-				NR_VM_NUMA_STAT_ITEMS],
-				node_page_state(pgdat, i));
+			seq_printf(m, "\n      %-12s %lu", node_stat_name(i),
+				   node_page_state(pgdat, i));
 		}
 	}
 	seq_printf(m,
@@ -1583,14 +1613,13 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
 	}
 
 	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
-		seq_printf(m, "\n      %-12s %lu", vmstat_text[i],
-				zone_page_state(zone, i));
+		seq_printf(m, "\n      %-12s %lu", zone_stat_name(i),
+			   zone_page_state(zone, i));
 
 #ifdef CONFIG_NUMA
 	for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
-		seq_printf(m, "\n      %-12s %lu",
-				vmstat_text[i + NR_VM_ZONE_STAT_ITEMS],
-				zone_numa_state_snapshot(zone, i));
+		seq_printf(m, "\n      %-12s %lu", numa_stat_name(i),
+			   zone_numa_state_snapshot(zone, i));
 #endif
 
 	seq_printf(m, "\n  pagesets");
@@ -1641,31 +1670,23 @@ static const struct seq_operations zoneinfo_op = {
 	.show	= zoneinfo_show,
 };
 
-enum writeback_stat_item {
-	NR_DIRTY_THRESHOLD,
-	NR_DIRTY_BG_THRESHOLD,
-	NR_VM_WRITEBACK_STAT_ITEMS,
-};
+#define NR_VMSTAT_ITEMS (NR_VM_ZONE_STAT_ITEMS + \
+			 NR_VM_NUMA_STAT_ITEMS + \
+			 NR_VM_NODE_STAT_ITEMS + \
+			 NR_VM_WRITEBACK_STAT_ITEMS + \
+			 (IS_ENABLED(CONFIG_VM_EVENT_COUNTERS) ? \
+			  NR_VM_EVENT_ITEMS : 0))
 
 static void *vmstat_start(struct seq_file *m, loff_t *pos)
 {
 	unsigned long *v;
-	int i, stat_items_size;
+	int i;
 
-	if (*pos >= ARRAY_SIZE(vmstat_text))
+	if (*pos >= NR_VMSTAT_ITEMS)
 		return NULL;
-	stat_items_size = NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long) +
-			  NR_VM_NUMA_STAT_ITEMS * sizeof(unsigned long) +
-			  NR_VM_NODE_STAT_ITEMS * sizeof(unsigned long) +
-			  NR_VM_WRITEBACK_STAT_ITEMS * sizeof(unsigned long);
-
-#ifdef CONFIG_VM_EVENT_COUNTERS
-	stat_items_size += sizeof(struct vm_event_state);
-#endif
 
-	BUILD_BUG_ON(stat_items_size !=
-		     ARRAY_SIZE(vmstat_text) * sizeof(unsigned long));
-	v = kmalloc(stat_items_size, GFP_KERNEL);
+	BUILD_BUG_ON(ARRAY_SIZE(vmstat_text) < NR_VMSTAT_ITEMS);
+	v = kmalloc_array(NR_VMSTAT_ITEMS, sizeof(unsigned long), GFP_KERNEL);
 	m->private = v;
 	if (!v)
 		return ERR_PTR(-ENOMEM);
@@ -1698,7 +1719,7 @@ static void *vmstat_start(struct seq_file *m, loff_t *pos)
 static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos)
 {
 	(*pos)++;
-	if (*pos >= ARRAY_SIZE(vmstat_text))
+	if (*pos >= NR_VMSTAT_ITEMS)
 		return NULL;
 	return (unsigned long *)m->private + *pos;
 }
@@ -1764,7 +1785,7 @@ int vmstat_refresh(struct ctl_table *table, int write,
 		val = atomic_long_read(&vm_zone_stat[i]);
 		if (val < 0) {
 			pr_warn("%s: %s %ld\n",
-				__func__, vmstat_text[i], val);
+				__func__, zone_stat_name(i), val);
 			err = -EINVAL;
 		}
 	}
@@ -1773,7 +1794,7 @@ int vmstat_refresh(struct ctl_table *table, int write,
 		val = atomic_long_read(&vm_numa_stat[i]);
 		if (val < 0) {
 			pr_warn("%s: %s %ld\n",
-				__func__, vmstat_text[i + NR_VM_ZONE_STAT_ITEMS], val);
+				__func__, numa_stat_name(i), val);
 			err = -EINVAL;
 		}
 	}
diff --git a/mm/z3fold.c b/mm/z3fold.c
index 6d3d3f698ebb..d48d0ec3bcdd 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -41,6 +41,7 @@
 #include <linux/workqueue.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
+#include <linux/rwlock.h>
 #include <linux/zpool.h>
 #include <linux/magic.h>
 
@@ -90,6 +91,7 @@ struct z3fold_buddy_slots {
 	 */
 	unsigned long slot[BUDDY_MASK + 1];
 	unsigned long pool; /* back link + flags */
+	rwlock_t lock;
 };
 #define HANDLE_FLAG_MASK	(0x03)
 
@@ -124,6 +126,7 @@ struct z3fold_header {
 	unsigned short start_middle;
 	unsigned short first_num:2;
 	unsigned short mapped_count:2;
+	unsigned short foreign_handles:2;
 };
 
 /**
@@ -178,6 +181,19 @@ enum z3fold_page_flags {
 	PAGE_CLAIMED, /* by either reclaim or free */
 };
 
+/*
+ * handle flags, go under HANDLE_FLAG_MASK
+ */
+enum z3fold_handle_flags {
+	HANDLES_ORPHANED = 0,
+};
+
+/*
+ * Forward declarations
+ */
+static struct z3fold_header *__z3fold_alloc(struct z3fold_pool *, size_t, bool);
+static void compact_page_work(struct work_struct *w);
+
 /*****************
  * Helpers
 *****************/
@@ -191,8 +207,6 @@ static int size_to_chunks(size_t size)
 #define for_each_unbuddied_list(_iter, _begin) \
 	for ((_iter) = (_begin); (_iter) < NCHUNKS; (_iter)++)
 
-static void compact_page_work(struct work_struct *w);
-
 static inline struct z3fold_buddy_slots *alloc_slots(struct z3fold_pool *pool,
 							gfp_t gfp)
 {
@@ -204,6 +218,7 @@ static inline struct z3fold_buddy_slots *alloc_slots(struct z3fold_pool *pool,
 	if (slots) {
 		memset(slots->slot, 0, sizeof(slots->slot));
 		slots->pool = (unsigned long)pool;
+		rwlock_init(&slots->lock);
 	}
 
 	return slots;
@@ -219,27 +234,108 @@ static inline struct z3fold_buddy_slots *handle_to_slots(unsigned long handle)
 	return (struct z3fold_buddy_slots *)(handle & ~(SLOTS_ALIGN - 1));
 }
 
+/* Lock a z3fold page */
+static inline void z3fold_page_lock(struct z3fold_header *zhdr)
+{
+	spin_lock(&zhdr->page_lock);
+}
+
+/* Try to lock a z3fold page */
+static inline int z3fold_page_trylock(struct z3fold_header *zhdr)
+{
+	return spin_trylock(&zhdr->page_lock);
+}
+
+/* Unlock a z3fold page */
+static inline void z3fold_page_unlock(struct z3fold_header *zhdr)
+{
+	spin_unlock(&zhdr->page_lock);
+}
+
+
+static inline struct z3fold_header *__get_z3fold_header(unsigned long handle,
+							bool lock)
+{
+	struct z3fold_buddy_slots *slots;
+	struct z3fold_header *zhdr;
+	int locked = 0;
+
+	if (!(handle & (1 << PAGE_HEADLESS))) {
+		slots = handle_to_slots(handle);
+		do {
+			unsigned long addr;
+
+			read_lock(&slots->lock);
+			addr = *(unsigned long *)handle;
+			zhdr = (struct z3fold_header *)(addr & PAGE_MASK);
+			if (lock)
+				locked = z3fold_page_trylock(zhdr);
+			read_unlock(&slots->lock);
+			if (locked)
+				break;
+			cpu_relax();
+		} while (lock);
+	} else {
+		zhdr = (struct z3fold_header *)(handle & PAGE_MASK);
+	}
+
+	return zhdr;
+}
+
+/* Returns the z3fold page where a given handle is stored */
+static inline struct z3fold_header *handle_to_z3fold_header(unsigned long h)
+{
+	return __get_z3fold_header(h, false);
+}
+
+/* return locked z3fold page if it's not headless */
+static inline struct z3fold_header *get_z3fold_header(unsigned long h)
+{
+	return __get_z3fold_header(h, true);
+}
+
+static inline void put_z3fold_header(struct z3fold_header *zhdr)
+{
+	struct page *page = virt_to_page(zhdr);
+
+	if (!test_bit(PAGE_HEADLESS, &page->private))
+		z3fold_page_unlock(zhdr);
+}
+
 static inline void free_handle(unsigned long handle)
 {
 	struct z3fold_buddy_slots *slots;
+	struct z3fold_header *zhdr;
 	int i;
 	bool is_free;
 
 	if (handle & (1 << PAGE_HEADLESS))
 		return;
 
-	WARN_ON(*(unsigned long *)handle == 0);
-	*(unsigned long *)handle = 0;
+	if (WARN_ON(*(unsigned long *)handle == 0))
+		return;
+
+	zhdr = handle_to_z3fold_header(handle);
 	slots = handle_to_slots(handle);
+	write_lock(&slots->lock);
+	*(unsigned long *)handle = 0;
+	write_unlock(&slots->lock);
+	if (zhdr->slots == slots)
+		return; /* simple case, nothing else to do */
+
+	/* we are freeing a foreign handle if we are here */
+	zhdr->foreign_handles--;
 	is_free = true;
+	read_lock(&slots->lock);
 	for (i = 0; i <= BUDDY_MASK; i++) {
 		if (slots->slot[i]) {
 			is_free = false;
 			break;
 		}
 	}
+	read_unlock(&slots->lock);
 
-	if (is_free) {
+	if (is_free && test_and_clear_bit(HANDLES_ORPHANED, &slots->pool)) {
 		struct z3fold_pool *pool = slots_to_pool(slots);
 
 		kmem_cache_free(pool->c_handle, slots);
@@ -322,6 +418,7 @@ static struct z3fold_header *init_z3fold_page(struct page *page, bool headless,
 	zhdr->first_num = 0;
 	zhdr->start_middle = 0;
 	zhdr->cpu = -1;
+	zhdr->foreign_handles = 0;
 	zhdr->slots = slots;
 	zhdr->pool = pool;
 	INIT_LIST_HEAD(&zhdr->buddy);
@@ -341,24 +438,6 @@ static void free_z3fold_page(struct page *page, bool headless)
 	__free_page(page);
 }
 
-/* Lock a z3fold page */
-static inline void z3fold_page_lock(struct z3fold_header *zhdr)
-{
-	spin_lock(&zhdr->page_lock);
-}
-
-/* Try to lock a z3fold page */
-static inline int z3fold_page_trylock(struct z3fold_header *zhdr)
-{
-	return spin_trylock(&zhdr->page_lock);
-}
-
-/* Unlock a z3fold page */
-static inline void z3fold_page_unlock(struct z3fold_header *zhdr)
-{
-	spin_unlock(&zhdr->page_lock);
-}
-
 /* Helper function to build the index */
 static inline int __idx(struct z3fold_header *zhdr, enum buddy bud)
 {
@@ -389,7 +468,9 @@ static unsigned long __encode_handle(struct z3fold_header *zhdr,
 	if (bud == LAST)
 		h |= (zhdr->last_chunks << BUDDY_SHIFT);
 
+	write_lock(&slots->lock);
 	slots->slot[idx] = h;
+	write_unlock(&slots->lock);
 	return (unsigned long)&slots->slot[idx];
 }
 
@@ -398,17 +479,6 @@ static unsigned long encode_handle(struct z3fold_header *zhdr, enum buddy bud)
 	return __encode_handle(zhdr, zhdr->slots, bud);
 }
 
-/* Returns the z3fold page where a given handle is stored */
-static inline struct z3fold_header *handle_to_z3fold_header(unsigned long h)
-{
-	unsigned long addr = h;
-
-	if (!(addr & (1 << PAGE_HEADLESS)))
-		addr = *(unsigned long *)h;
-
-	return (struct z3fold_header *)(addr & PAGE_MASK);
-}
-
 /* only for LAST bud, returns zero otherwise */
 static unsigned short handle_to_chunks(unsigned long handle)
 {
@@ -442,6 +512,8 @@ static void __release_z3fold_page(struct z3fold_header *zhdr, bool locked)
 {
 	struct page *page = virt_to_page(zhdr);
 	struct z3fold_pool *pool = zhdr_to_pool(zhdr);
+	bool is_free = true;
+	int i;
 
 	WARN_ON(!list_empty(&zhdr->buddy));
 	set_bit(PAGE_STALE, &page->private);
@@ -450,8 +522,25 @@ static void __release_z3fold_page(struct z3fold_header *zhdr, bool locked)
 	if (!list_empty(&page->lru))
 		list_del_init(&page->lru);
 	spin_unlock(&pool->lock);
+
+	/* If there are no foreign handles, free the handles array */
+	read_lock(&zhdr->slots->lock);
+	for (i = 0; i <= BUDDY_MASK; i++) {
+		if (zhdr->slots->slot[i]) {
+			is_free = false;
+			break;
+		}
+	}
+	read_unlock(&zhdr->slots->lock);
+
+	if (is_free)
+		kmem_cache_free(pool->c_handle, zhdr->slots);
+	else
+		set_bit(HANDLES_ORPHANED, &zhdr->slots->pool);
+
 	if (locked)
 		z3fold_page_unlock(zhdr);
+
 	spin_lock(&pool->stale_lock);
 	list_add(&zhdr->buddy, &pool->stale);
 	queue_work(pool->release_wq, &pool->work);
@@ -479,6 +568,7 @@ static void release_z3fold_page_locked_list(struct kref *ref)
 	struct z3fold_header *zhdr = container_of(ref, struct z3fold_header,
 					       refcount);
 	struct z3fold_pool *pool = zhdr_to_pool(zhdr);
+
 	spin_lock(&pool->lock);
 	list_del_init(&zhdr->buddy);
 	spin_unlock(&pool->lock);
@@ -559,6 +649,113 @@ static inline void *mchunk_memmove(struct z3fold_header *zhdr,
 		       zhdr->middle_chunks << CHUNK_SHIFT);
 }
 
+static inline bool buddy_single(struct z3fold_header *zhdr)
+{
+	return !((zhdr->first_chunks && zhdr->middle_chunks) ||
+			(zhdr->first_chunks && zhdr->last_chunks) ||
+			(zhdr->middle_chunks && zhdr->last_chunks));
+}
+
+static struct z3fold_header *compact_single_buddy(struct z3fold_header *zhdr)
+{
+	struct z3fold_pool *pool = zhdr_to_pool(zhdr);
+	void *p = zhdr;
+	unsigned long old_handle = 0;
+	size_t sz = 0;
+	struct z3fold_header *new_zhdr = NULL;
+	int first_idx = __idx(zhdr, FIRST);
+	int middle_idx = __idx(zhdr, MIDDLE);
+	int last_idx = __idx(zhdr, LAST);
+
+	/*
+	 * No need to protect slots here -- all the slots are "local" and
+	 * the page lock is already taken
+	 */
+	if (zhdr->first_chunks && zhdr->slots->slot[first_idx]) {
+		p += ZHDR_SIZE_ALIGNED;
+		sz = zhdr->first_chunks << CHUNK_SHIFT;
+		old_handle = (unsigned long)&zhdr->slots->slot[first_idx];
+	} else if (zhdr->middle_chunks && zhdr->slots->slot[middle_idx]) {
+		p += zhdr->start_middle << CHUNK_SHIFT;
+		sz = zhdr->middle_chunks << CHUNK_SHIFT;
+		old_handle = (unsigned long)&zhdr->slots->slot[middle_idx];
+	} else if (zhdr->last_chunks && zhdr->slots->slot[last_idx]) {
+		p += PAGE_SIZE - (zhdr->last_chunks << CHUNK_SHIFT);
+		sz = zhdr->last_chunks << CHUNK_SHIFT;
+		old_handle = (unsigned long)&zhdr->slots->slot[last_idx];
+	}
+
+	if (sz > 0) {
+		enum buddy new_bud = HEADLESS;
+		short chunks = size_to_chunks(sz);
+		void *q;
+
+		new_zhdr = __z3fold_alloc(pool, sz, false);
+		if (!new_zhdr)
+			return NULL;
+
+		if (WARN_ON(new_zhdr == zhdr))
+			goto out_fail;
+
+		if (new_zhdr->first_chunks == 0) {
+			if (new_zhdr->middle_chunks != 0 &&
+					chunks >= new_zhdr->start_middle) {
+				new_bud = LAST;
+			} else {
+				new_bud = FIRST;
+			}
+		} else if (new_zhdr->last_chunks == 0) {
+			new_bud = LAST;
+		} else if (new_zhdr->middle_chunks == 0) {
+			new_bud = MIDDLE;
+		}
+		q = new_zhdr;
+		switch (new_bud) {
+		case FIRST:
+			new_zhdr->first_chunks = chunks;
+			q += ZHDR_SIZE_ALIGNED;
+			break;
+		case MIDDLE:
+			new_zhdr->middle_chunks = chunks;
+			new_zhdr->start_middle =
+				new_zhdr->first_chunks + ZHDR_CHUNKS;
+			q += new_zhdr->start_middle << CHUNK_SHIFT;
+			break;
+		case LAST:
+			new_zhdr->last_chunks = chunks;
+			q += PAGE_SIZE - (new_zhdr->last_chunks << CHUNK_SHIFT);
+			break;
+		default:
+			goto out_fail;
+		}
+		new_zhdr->foreign_handles++;
+		memcpy(q, p, sz);
+		write_lock(&zhdr->slots->lock);
+		*(unsigned long *)old_handle = (unsigned long)new_zhdr +
+			__idx(new_zhdr, new_bud);
+		if (new_bud == LAST)
+			*(unsigned long *)old_handle |=
+					(new_zhdr->last_chunks << BUDDY_SHIFT);
+		write_unlock(&zhdr->slots->lock);
+		add_to_unbuddied(pool, new_zhdr);
+		z3fold_page_unlock(new_zhdr);
+	}
+
+	return new_zhdr;
+
+out_fail:
+	if (new_zhdr) {
+		if (kref_put(&new_zhdr->refcount, release_z3fold_page_locked))
+			atomic64_dec(&pool->pages_nr);
+		else {
+			add_to_unbuddied(pool, new_zhdr);
+			z3fold_page_unlock(new_zhdr);
+		}
+	}
+	return NULL;
+
+}
+
 #define BIG_CHUNK_GAP	3
 /* Has to be called with lock held */
 static int z3fold_compact_page(struct z3fold_header *zhdr)
@@ -638,6 +835,15 @@ static void do_compact_page(struct z3fold_header *zhdr, bool locked)
 		return;
 	}
 
+	if (!zhdr->foreign_handles && buddy_single(zhdr) &&
+			compact_single_buddy(zhdr)) {
+		if (kref_put(&zhdr->refcount, release_z3fold_page_locked))
+			atomic64_dec(&pool->pages_nr);
+		else
+			z3fold_page_unlock(zhdr);
+		return;
+	}
+
 	z3fold_compact_page(zhdr);
 	add_to_unbuddied(pool, zhdr);
 	z3fold_page_unlock(zhdr);
@@ -690,7 +896,8 @@ lookup:
 		spin_unlock(&pool->lock);
 
 		page = virt_to_page(zhdr);
-		if (test_bit(NEEDS_COMPACTING, &page->private)) {
+		if (test_bit(NEEDS_COMPACTING, &page->private) ||
+		    test_bit(PAGE_CLAIMED, &page->private)) {
 			z3fold_page_unlock(zhdr);
 			zhdr = NULL;
 			put_cpu_ptr(pool->unbuddied);
@@ -734,7 +941,8 @@ lookup:
 			spin_unlock(&pool->lock);
 
 			page = virt_to_page(zhdr);
-			if (test_bit(NEEDS_COMPACTING, &page->private)) {
+			if (test_bit(NEEDS_COMPACTING, &page->private) ||
+			    test_bit(PAGE_CLAIMED, &page->private)) {
 				z3fold_page_unlock(zhdr);
 				zhdr = NULL;
 				if (can_sleep)
@@ -1000,7 +1208,7 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 	enum buddy bud;
 	bool page_claimed;
 
-	zhdr = handle_to_z3fold_header(handle);
+	zhdr = get_z3fold_header(handle);
 	page = virt_to_page(zhdr);
 	page_claimed = test_and_set_bit(PAGE_CLAIMED, &page->private);
 
@@ -1014,6 +1222,7 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 			spin_lock(&pool->lock);
 			list_del(&page->lru);
 			spin_unlock(&pool->lock);
+			put_z3fold_header(zhdr);
 			free_z3fold_page(page, true);
 			atomic64_dec(&pool->pages_nr);
 		}
@@ -1021,7 +1230,6 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 	}
 
 	/* Non-headless case */
-	z3fold_page_lock(zhdr);
 	bud = handle_to_buddy(handle);
 
 	switch (bud) {
@@ -1037,11 +1245,11 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 	default:
 		pr_err("%s: unknown bud %d\n", __func__, bud);
 		WARN_ON(1);
-		z3fold_page_unlock(zhdr);
+		put_z3fold_header(zhdr);
+		clear_bit(PAGE_CLAIMED, &page->private);
 		return;
 	}
 
-	free_handle(handle);
 	if (kref_put(&zhdr->refcount, release_z3fold_page_locked_list)) {
 		atomic64_dec(&pool->pages_nr);
 		return;
@@ -1051,9 +1259,10 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 		z3fold_page_unlock(zhdr);
 		return;
 	}
+	free_handle(handle);
 	if (unlikely(PageIsolated(page)) ||
 	    test_and_set_bit(NEEDS_COMPACTING, &page->private)) {
-		z3fold_page_unlock(zhdr);
+		put_z3fold_header(zhdr);
 		clear_bit(PAGE_CLAIMED, &page->private);
 		return;
 	}
@@ -1063,14 +1272,14 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 		spin_unlock(&pool->lock);
 		zhdr->cpu = -1;
 		kref_get(&zhdr->refcount);
-		do_compact_page(zhdr, true);
 		clear_bit(PAGE_CLAIMED, &page->private);
+		do_compact_page(zhdr, true);
 		return;
 	}
 	kref_get(&zhdr->refcount);
-	queue_work_on(zhdr->cpu, pool->compact_wq, &zhdr->work);
 	clear_bit(PAGE_CLAIMED, &page->private);
-	z3fold_page_unlock(zhdr);
+	queue_work_on(zhdr->cpu, pool->compact_wq, &zhdr->work);
+	put_z3fold_header(zhdr);
 }
 
 /**
@@ -1111,11 +1320,10 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
  */
 static int z3fold_reclaim_page(struct z3fold_pool *pool, unsigned int retries)
 {
-	int i, ret = 0;
+	int i, ret = -1;
 	struct z3fold_header *zhdr = NULL;
 	struct page *page = NULL;
 	struct list_head *pos;
-	struct z3fold_buddy_slots slots;
 	unsigned long first_handle = 0, middle_handle = 0, last_handle = 0;
 
 	spin_lock(&pool->lock);
@@ -1153,6 +1361,12 @@ static int z3fold_reclaim_page(struct z3fold_pool *pool, unsigned int retries)
 				zhdr = NULL;
 				continue; /* can't evict at this point */
 			}
+			if (zhdr->foreign_handles) {
+				clear_bit(PAGE_CLAIMED, &page->private);
+				z3fold_page_unlock(zhdr);
+				zhdr = NULL;
+				continue; /* can't evict such page */
+			}
 			kref_get(&zhdr->refcount);
 			list_del_init(&zhdr->buddy);
 			zhdr->cpu = -1;
@@ -1176,39 +1390,38 @@ static int z3fold_reclaim_page(struct z3fold_pool *pool, unsigned int retries)
 			last_handle = 0;
 			middle_handle = 0;
 			if (zhdr->first_chunks)
-				first_handle = __encode_handle(zhdr, &slots,
-								FIRST);
+				first_handle = encode_handle(zhdr, FIRST);
 			if (zhdr->middle_chunks)
-				middle_handle = __encode_handle(zhdr, &slots,
-								MIDDLE);
+				middle_handle = encode_handle(zhdr, MIDDLE);
 			if (zhdr->last_chunks)
-				last_handle = __encode_handle(zhdr, &slots,
-								LAST);
+				last_handle = encode_handle(zhdr, LAST);
 			/*
 			 * it's safe to unlock here because we hold a
 			 * reference to this page
 			 */
 			z3fold_page_unlock(zhdr);
 		} else {
-			first_handle = __encode_handle(zhdr, &slots, HEADLESS);
+			first_handle = encode_handle(zhdr, HEADLESS);
 			last_handle = middle_handle = 0;
 		}
-
 		/* Issue the eviction callback(s) */
 		if (middle_handle) {
 			ret = pool->ops->evict(pool, middle_handle);
 			if (ret)
 				goto next;
+			free_handle(middle_handle);
 		}
 		if (first_handle) {
 			ret = pool->ops->evict(pool, first_handle);
 			if (ret)
 				goto next;
+			free_handle(first_handle);
 		}
 		if (last_handle) {
 			ret = pool->ops->evict(pool, last_handle);
 			if (ret)
 				goto next;
+			free_handle(last_handle);
 		}
 next:
 		if (test_bit(PAGE_HEADLESS, &page->private)) {
@@ -1264,14 +1477,13 @@ static void *z3fold_map(struct z3fold_pool *pool, unsigned long handle)
 	void *addr;
 	enum buddy buddy;
 
-	zhdr = handle_to_z3fold_header(handle);
+	zhdr = get_z3fold_header(handle);
 	addr = zhdr;
 	page = virt_to_page(zhdr);
 
 	if (test_bit(PAGE_HEADLESS, &page->private))
 		goto out;
 
-	z3fold_page_lock(zhdr);
 	buddy = handle_to_buddy(handle);
 	switch (buddy) {
 	case FIRST:
@@ -1293,8 +1505,8 @@ static void *z3fold_map(struct z3fold_pool *pool, unsigned long handle)
 
 	if (addr)
 		zhdr->mapped_count++;
-	z3fold_page_unlock(zhdr);
 out:
+	put_z3fold_header(zhdr);
 	return addr;
 }
 
@@ -1309,18 +1521,17 @@ static void z3fold_unmap(struct z3fold_pool *pool, unsigned long handle)
 	struct page *page;
 	enum buddy buddy;
 
-	zhdr = handle_to_z3fold_header(handle);
+	zhdr = get_z3fold_header(handle);
 	page = virt_to_page(zhdr);
 
 	if (test_bit(PAGE_HEADLESS, &page->private))
 		return;
 
-	z3fold_page_lock(zhdr);
 	buddy = handle_to_buddy(handle);
 	if (buddy == MIDDLE)
 		clear_bit(MIDDLE_CHUNK_MAPPED, &page->private);
 	zhdr->mapped_count--;
-	z3fold_page_unlock(zhdr);
+	put_z3fold_header(zhdr);
 }
 
 /**
@@ -1352,19 +1563,21 @@ static bool z3fold_page_isolate(struct page *page, isolate_mode_t mode)
 	    test_bit(PAGE_STALE, &page->private))
 		goto out;
 
+	if (zhdr->mapped_count != 0 || zhdr->foreign_handles != 0)
+		goto out;
+
 	pool = zhdr_to_pool(zhdr);
+	spin_lock(&pool->lock);
+	if (!list_empty(&zhdr->buddy))
+		list_del_init(&zhdr->buddy);
+	if (!list_empty(&page->lru))
+		list_del_init(&page->lru);
+	spin_unlock(&pool->lock);
+
+	kref_get(&zhdr->refcount);
+	z3fold_page_unlock(zhdr);
+	return true;
 
-	if (zhdr->mapped_count == 0) {
-		kref_get(&zhdr->refcount);
-		if (!list_empty(&zhdr->buddy))
-			list_del_init(&zhdr->buddy);
-		spin_lock(&pool->lock);
-		if (!list_empty(&page->lru))
-			list_del(&page->lru);
-		spin_unlock(&pool->lock);
-		z3fold_page_unlock(zhdr);
-		return true;
-	}
 out:
 	z3fold_page_unlock(zhdr);
 	return false;
@@ -1387,7 +1600,7 @@ static int z3fold_page_migrate(struct address_space *mapping, struct page *newpa
 	if (!z3fold_page_trylock(zhdr)) {
 		return -EAGAIN;
 	}
-	if (zhdr->mapped_count != 0) {
+	if (zhdr->mapped_count != 0 || zhdr->foreign_handles != 0) {
 		z3fold_page_unlock(zhdr);
 		return -EBUSY;
 	}
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index b71a39ded930..39e14d5edaf1 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -51,7 +51,7 @@ static BLOCKING_NOTIFIER_HEAD(rpc_pipefs_notifier_list);
 
 int rpc_pipefs_notifier_register(struct notifier_block *nb)
 {
-	return blocking_notifier_chain_cond_register(&rpc_pipefs_notifier_list, nb);
+	return blocking_notifier_chain_register(&rpc_pipefs_notifier_list, nb);
 }
 EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_register);
 
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index e9995b880f84..a85d719df1f4 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -607,6 +607,20 @@ foreach my $entry (keys %deprecated_apis) {
 }
 $deprecated_apis_search = "(?:${deprecated_apis_search})";
 
+our %deprecated_string_apis = (
+	"strcpy"		=> "stracpy or strscpy",
+	"strlcpy"		=> "stracpy or strscpy",
+	"strncpy"		=> "stracpy or strscpy - for non-NUL-terminated uses, strncpy dest should be __nonstring",
+);
+
+#Create a search pattern for all these strings apis to speed up a loop below
+our $deprecated_string_apis_search = "";
+foreach my $entry (keys %deprecated_string_apis) {
+        $deprecated_string_apis_search .= '|' if ($deprecated_string_apis_search ne "");
+        $deprecated_string_apis_search .= $entry;
+}
+$deprecated_string_apis_search = "(?:${deprecated_string_apis_search})";
+
 our $mode_perms_world_writable = qr{
 	S_IWUGO		|
 	S_IWOTH		|
@@ -5038,8 +5052,9 @@ sub process {
 			    $var =~ /[A-Z][a-z]|[a-z][A-Z]/ &&
 #Ignore Page<foo> variants
 			    $var !~ /^(?:Clear|Set|TestClear|TestSet|)Page[A-Z]/ &&
-#Ignore SI style variants like nS, mV and dB (ie: max_uV, regulator_min_uA_show)
-			    $var !~ /^(?:[a-z_]*?)_?[a-z][A-Z](?:_[a-z_]+)?$/ &&
+#Ignore SI style variants like nS, mV and dB
+#(ie: max_uV, regulator_min_uA_show, RANGE_mA_VALUE)
+			    $var !~ /^(?:[a-z0-9_]*|[A-Z0-9_]*)?_?[a-z][A-Z](?:_[a-z0-9_]+|_[A-Z0-9_]+)?$/ &&
 #Ignore some three character SI units explicitly, like MiB and KHz
 			    $var !~ /^(?:[a-z_]*?)_?(?:[KMGT]iB|[KMGT]?Hz)(?:_[a-z_]+)?$/) {
 				while ($var =~ m{($Ident)}g) {
@@ -6484,6 +6499,16 @@ sub process {
 			     "Deprecated use of '$deprecated_api', prefer '$new_api' instead\n" . $herecurr);
 		}
 
+# check for string deprecated apis
+		if ($line =~ /\b($deprecated_string_apis_search)\b\s*\(/) {
+			my $deprecated_string_api = $1;
+			my $new_api = $deprecated_string_apis{$deprecated_string_api};
+			my $msg_level = \&WARN;
+			$msg_level = \&CHK if ($file);
+			&{$msg_level}("DEPRECATED_API",
+				      "Deprecated use of '$deprecated_string_api', prefer '$new_api' instead\n" . $herecurr);
+		}
+
 # check for various structs that are normally const (ops, kgdb, device_tree)
 # and avoid what seem like struct definitions 'struct foo {'
 		if ($line !~ /\bconst\b/ &&
diff --git a/scripts/get_maintainer.pl b/scripts/get_maintainer.pl
index 5ef59214c555..34085d146fa2 100755
--- a/scripts/get_maintainer.pl
+++ b/scripts/get_maintainer.pl
@@ -26,6 +26,7 @@ my $email = 1;
 my $email_usename = 1;
 my $email_maintainer = 1;
 my $email_reviewer = 1;
+my $email_fixes = 1;
 my $email_list = 1;
 my $email_moderated_list = 1;
 my $email_subscriber_list = 0;
@@ -249,6 +250,7 @@ if (!GetOptions(
 		'r!' => \$email_reviewer,
 		'n!' => \$email_usename,
 		'l!' => \$email_list,
+		'fixes!' => \$email_fixes,
 		'moderated!' => \$email_moderated_list,
 		's!' => \$email_subscriber_list,
 		'multiline!' => \$output_multiline,
@@ -503,6 +505,7 @@ sub read_mailmap {
 ## use the filenames on the command line or find the filenames in the patchfiles
 
 my @files = ();
+my @fixes = ();			# If a patch description includes Fixes: lines
 my @range = ();
 my @keyword_tvi = ();
 my @file_emails = ();
@@ -568,6 +571,8 @@ foreach my $file (@ARGV) {
 		my $filename2 = $2;
 		push(@files, $filename1);
 		push(@files, $filename2);
+	    } elsif (m/^Fixes:\s+([0-9a-fA-F]{6,40})/) {
+		push(@fixes, $1) if ($email_fixes);
 	    } elsif (m/^\+\+\+\s+(\S+)/ or m/^---\s+(\S+)/) {
 		my $filename = $1;
 		$filename =~ s@^[^/]*/@@;
@@ -598,6 +603,7 @@ foreach my $file (@ARGV) {
 }
 
 @file_emails = uniq(@file_emails);
+@fixes = uniq(@fixes);
 
 my %email_hash_name;
 my %email_hash_address;
@@ -612,7 +618,6 @@ my %deduplicate_name_hash = ();
 my %deduplicate_address_hash = ();
 
 my @maintainers = get_maintainers();
-
 if (@maintainers) {
     @maintainers = merge_email(@maintainers);
     output(@maintainers);
@@ -927,6 +932,10 @@ sub get_maintainers {
 	}
     }
 
+    foreach my $fix (@fixes) {
+	vcs_add_commit_signers($fix, "blamed_fixes");
+    }
+
     foreach my $email (@email_to, @list_to) {
 	$email->[0] = deduplicate_email($email->[0]);
     }
@@ -1031,6 +1040,7 @@ MAINTAINER field selection options:
     --roles => show roles (status:subsystem, git-signer, list, etc...)
     --rolestats => show roles and statistics (commits/total_commits, %)
     --file-emails => add email addresses found in -f file (default: 0 (off))
+    --fixes => for patches, add signatures of commits with 'Fixes: <commit>' (default: 1 (on))
   --scm => print SCM tree(s) if any
   --status => print status if any
   --subsystem => print subsystem name if any
@@ -1730,6 +1740,32 @@ sub vcs_is_hg {
     return $vcs_used == 2;
 }
 
+sub vcs_add_commit_signers {
+    return if (!vcs_exists());
+
+    my ($commit, $desc) = @_;
+    my $commit_count = 0;
+    my $commit_authors_ref;
+    my $commit_signers_ref;
+    my $stats_ref;
+    my @commit_authors = ();
+    my @commit_signers = ();
+    my $cmd;
+
+    $cmd = $VCS_cmds{"find_commit_signers_cmd"};
+    $cmd =~ s/(\$\w+)/$1/eeg;	#substitute variables in $cmd
+
+    ($commit_count, $commit_signers_ref, $commit_authors_ref, $stats_ref) = vcs_find_signers($cmd, "");
+    @commit_authors = @{$commit_authors_ref} if defined $commit_authors_ref;
+    @commit_signers = @{$commit_signers_ref} if defined $commit_signers_ref;
+
+    foreach my $signer (@commit_signers) {
+	$signer = deduplicate_email($signer);
+    }
+
+    vcs_assign($desc, 1, @commit_signers);
+}
+
 sub interactive_get_maintainers {
     my ($list_ref) = @_;
     my @list = @$list_ref;
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 2c6f7994a0aa..d65f59669f7c 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -12,6 +12,7 @@ TARGETS += efivarfs
 TARGETS += exec
 TARGETS += filesystems
 TARGETS += filesystems/binderfs
+TARGETS += filesystems/epoll
 TARGETS += firmware
 TARGETS += ftrace
 TARGETS += futex
diff --git a/tools/testing/selftests/filesystems/epoll/.gitignore b/tools/testing/selftests/filesystems/epoll/.gitignore
new file mode 100644
index 000000000000..9ae8db44ec14
--- /dev/null
+++ b/tools/testing/selftests/filesystems/epoll/.gitignore
@@ -0,0 +1 @@
+epoll_wakeup_test
diff --git a/tools/testing/selftests/filesystems/epoll/Makefile b/tools/testing/selftests/filesystems/epoll/Makefile
new file mode 100644
index 000000000000..e62f3d4f68da
--- /dev/null
+++ b/tools/testing/selftests/filesystems/epoll/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+CFLAGS += -I../../../../../usr/include/
+LDFLAGS += -lpthread
+TEST_GEN_PROGS := epoll_wakeup_test
+
+include ../../lib.mk
diff --git a/tools/testing/selftests/filesystems/epoll/epoll_wakeup_test.c b/tools/testing/selftests/filesystems/epoll/epoll_wakeup_test.c
new file mode 100644
index 000000000000..37a04dab56f0
--- /dev/null
+++ b/tools/testing/selftests/filesystems/epoll/epoll_wakeup_test.c
@@ -0,0 +1,3074 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+#include <poll.h>
+#include <unistd.h>
+#include <signal.h>
+#include <pthread.h>
+#include <sys/epoll.h>
+#include <sys/socket.h>
+#include "../../kselftest_harness.h"
+
+struct epoll_mtcontext
+{
+	int efd[3];
+	int sfd[4];
+	int count;
+
+	pthread_t main;
+	pthread_t waiter;
+};
+
+static void signal_handler(int signum)
+{
+}
+
+static void kill_timeout(struct epoll_mtcontext *ctx)
+{
+	usleep(1000000);
+	pthread_kill(ctx->main, SIGUSR1);
+	pthread_kill(ctx->waiter, SIGUSR1);
+}
+
+static void *waiter_entry1a(void *data)
+{
+	struct epoll_event e;
+	struct epoll_mtcontext *ctx = data;
+
+	if (epoll_wait(ctx->efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx->count, 1);
+
+	return NULL;
+}
+
+static void *waiter_entry1ap(void *data)
+{
+	struct pollfd pfd;
+	struct epoll_event e;
+	struct epoll_mtcontext *ctx = data;
+
+	pfd.fd = ctx->efd[0];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx->efd[0], &e, 1, 0) > 0)
+			__sync_fetch_and_add(&ctx->count, 1);
+	}
+
+	return NULL;
+}
+
+static void *waiter_entry1o(void *data)
+{
+	struct epoll_event e;
+	struct epoll_mtcontext *ctx = data;
+
+	if (epoll_wait(ctx->efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_or(&ctx->count, 1);
+
+	return NULL;
+}
+
+static void *waiter_entry1op(void *data)
+{
+	struct pollfd pfd;
+	struct epoll_event e;
+	struct epoll_mtcontext *ctx = data;
+
+	pfd.fd = ctx->efd[0];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx->efd[0], &e, 1, 0) > 0)
+			__sync_fetch_and_or(&ctx->count, 1);
+	}
+
+	return NULL;
+}
+
+static void *waiter_entry2a(void *data)
+{
+	struct epoll_event events[2];
+	struct epoll_mtcontext *ctx = data;
+
+	if (epoll_wait(ctx->efd[0], events, 2, -1) > 0)
+		__sync_fetch_and_add(&ctx->count, 1);
+
+	return NULL;
+}
+
+static void *waiter_entry2ap(void *data)
+{
+	struct pollfd pfd;
+	struct epoll_event events[2];
+	struct epoll_mtcontext *ctx = data;
+
+	pfd.fd = ctx->efd[0];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx->efd[0], events, 2, 0) > 0)
+			__sync_fetch_and_add(&ctx->count, 1);
+	}
+
+	return NULL;
+}
+
+static void *emitter_entry1(void *data)
+{
+	struct epoll_mtcontext *ctx = data;
+
+	usleep(100000);
+	write(ctx->sfd[1], "w", 1);
+
+	kill_timeout(ctx);
+
+	return NULL;
+}
+
+static void *emitter_entry2(void *data)
+{
+	struct epoll_mtcontext *ctx = data;
+
+	usleep(100000);
+	write(ctx->sfd[1], "w", 1);
+	write(ctx->sfd[3], "w", 1);
+
+	kill_timeout(ctx);
+
+	return NULL;
+}
+
+/*
+ *          t0
+ *           | (ew)
+ *          e0
+ *           | (lt)
+ *          s0
+ */
+TEST(epoll1)
+{
+	int efd;
+	int sfd[2];
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, sfd), 0);
+
+	efd = epoll_create(1);
+	ASSERT_GE(efd, 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	EXPECT_EQ(epoll_wait(efd, &e, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd, &e, 1, 0), 1);
+
+	close(efd);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *          t0
+ *           | (ew)
+ *          e0
+ *           | (et)
+ *          s0
+ */
+TEST(epoll2)
+{
+	int efd;
+	int sfd[2];
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, sfd), 0);
+
+	efd = epoll_create(1);
+	ASSERT_GE(efd, 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	EXPECT_EQ(epoll_wait(efd, &e, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd, &e, 1, 0), 0);
+
+	close(efd);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *           t0
+ *            | (ew)
+ *           e0
+ *     (lt) /  \ (lt)
+ *        s0    s2
+ */
+TEST(epoll3)
+{
+	int efd;
+	int sfd[4];
+	struct epoll_event events[2];
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[2]), 0);
+
+	efd = epoll_create(1);
+	ASSERT_GE(efd, 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[0], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[2], events), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+	ASSERT_EQ(write(sfd[3], "w", 1), 1);
+
+	EXPECT_EQ(epoll_wait(efd, events, 2, 0), 2);
+	EXPECT_EQ(epoll_wait(efd, events, 2, 0), 2);
+
+	close(efd);
+	close(sfd[0]);
+	close(sfd[1]);
+	close(sfd[2]);
+	close(sfd[3]);
+}
+
+/*
+ *           t0
+ *            | (ew)
+ *           e0
+ *     (et) /  \ (et)
+ *        s0    s2
+ */
+TEST(epoll4)
+{
+	int efd;
+	int sfd[4];
+	struct epoll_event events[2];
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[2]), 0);
+
+	efd = epoll_create(1);
+	ASSERT_GE(efd, 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[0], events), 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[2], events), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+	ASSERT_EQ(write(sfd[3], "w", 1), 1);
+
+	EXPECT_EQ(epoll_wait(efd, events, 2, 0), 2);
+	EXPECT_EQ(epoll_wait(efd, events, 2, 0), 0);
+
+	close(efd);
+	close(sfd[0]);
+	close(sfd[1]);
+	close(sfd[2]);
+	close(sfd[3]);
+}
+
+/*
+ *          t0
+ *           | (p)
+ *          e0
+ *           | (lt)
+ *          s0
+ */
+TEST(epoll5)
+{
+	int efd;
+	int sfd[2];
+	struct pollfd pfd;
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[0]), 0);
+
+	efd = epoll_create(1);
+	ASSERT_GE(efd, 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	pfd.fd = efd;
+	pfd.events = POLLIN;
+	ASSERT_EQ(poll(&pfd, 1, 0), 1);
+	ASSERT_EQ(epoll_wait(efd, &e, 1, 0), 1);
+
+	pfd.fd = efd;
+	pfd.events = POLLIN;
+	ASSERT_EQ(poll(&pfd, 1, 0), 1);
+	ASSERT_EQ(epoll_wait(efd, &e, 1, 0), 1);
+
+	close(efd);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *          t0
+ *           | (p)
+ *          e0
+ *           | (et)
+ *          s0
+ */
+TEST(epoll6)
+{
+	int efd;
+	int sfd[2];
+	struct pollfd pfd;
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[0]), 0);
+
+	efd = epoll_create(1);
+	ASSERT_GE(efd, 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	pfd.fd = efd;
+	pfd.events = POLLIN;
+	ASSERT_EQ(poll(&pfd, 1, 0), 1);
+	ASSERT_EQ(epoll_wait(efd, &e, 1, 0), 1);
+
+	pfd.fd = efd;
+	pfd.events = POLLIN;
+	ASSERT_EQ(poll(&pfd, 1, 0), 0);
+	ASSERT_EQ(epoll_wait(efd, &e, 1, 0), 0);
+
+	close(efd);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *           t0
+ *            | (p)
+ *           e0
+ *     (lt) /  \ (lt)
+ *        s0    s2
+ */
+
+TEST(epoll7)
+{
+	int efd;
+	int sfd[4];
+	struct pollfd pfd;
+	struct epoll_event events[2];
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[2]), 0);
+
+	efd = epoll_create(1);
+	ASSERT_GE(efd, 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[0], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[2], events), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+	ASSERT_EQ(write(sfd[3], "w", 1), 1);
+
+	pfd.fd = efd;
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd, events, 2, 0), 2);
+
+	pfd.fd = efd;
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd, events, 2, 0), 2);
+
+	close(efd);
+	close(sfd[0]);
+	close(sfd[1]);
+	close(sfd[2]);
+	close(sfd[3]);
+}
+
+/*
+ *           t0
+ *            | (p)
+ *           e0
+ *     (et) /  \ (et)
+ *        s0    s2
+ */
+TEST(epoll8)
+{
+	int efd;
+	int sfd[4];
+	struct pollfd pfd;
+	struct epoll_event events[2];
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[2]), 0);
+
+	efd = epoll_create(1);
+	ASSERT_GE(efd, 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[0], events), 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd, EPOLL_CTL_ADD, sfd[2], events), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+	ASSERT_EQ(write(sfd[3], "w", 1), 1);
+
+	pfd.fd = efd;
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd, events, 2, 0), 2);
+
+	pfd.fd = efd;
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 0);
+	EXPECT_EQ(epoll_wait(efd, events, 2, 0), 0);
+
+	close(efd);
+	close(sfd[0]);
+	close(sfd[1]);
+	close(sfd[2]);
+	close(sfd[3]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (ew)
+ *           e0
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll9)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (ew)
+ *           e0
+ *            | (et)
+ *           s0
+ */
+TEST(epoll10)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 1);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (ew)
+ *           e0
+ *     (lt) /  \ (lt)
+ *        s0    s2
+ */
+TEST(epoll11)
+{
+	pthread_t emitter;
+	struct epoll_event events[2];
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[2]), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[0], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[2], events), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry2a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry2, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], events, 2, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+	close(ctx.sfd[2]);
+	close(ctx.sfd[3]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (ew)
+ *           e0
+ *     (et) /  \ (et)
+ *        s0    s2
+ */
+TEST(epoll12)
+{
+	pthread_t emitter;
+	struct epoll_event events[2];
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[2]), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[0], events), 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[2], events), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry2, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], events, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+	close(ctx.sfd[2]);
+	close(ctx.sfd[3]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (p)
+ *           e0
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll13)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (p)
+ *           e0
+ *            | (et)
+ *           s0
+ */
+TEST(epoll14)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 1);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (p)
+ *           e0
+ *     (lt) /  \ (lt)
+ *        s0    s2
+ */
+TEST(epoll15)
+{
+	pthread_t emitter;
+	struct epoll_event events[2];
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[2]), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[0], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[2], events), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry2ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry2, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], events, 2, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+	close(ctx.sfd[2]);
+	close(ctx.sfd[3]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (p)
+ *           e0
+ *     (et) /  \ (et)
+ *        s0    s2
+ */
+TEST(epoll16)
+{
+	pthread_t emitter;
+	struct epoll_event events[2];
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[2]), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[0], events), 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.sfd[2], events), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry2, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], events, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+	close(ctx.sfd[2]);
+	close(ctx.sfd[3]);
+}
+
+/*
+ *          t0
+ *           | (ew)
+ *          e0
+ *           | (lt)
+ *          e1
+ *           | (lt)
+ *          s0
+ */
+TEST(epoll17)
+{
+	int efd[2];
+	int sfd[2];
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, sfd), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *          t0
+ *           | (ew)
+ *          e0
+ *           | (lt)
+ *          e1
+ *           | (et)
+ *          s0
+ */
+TEST(epoll18)
+{
+	int efd[2];
+	int sfd[2];
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, sfd), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *           t0
+ *            | (ew)
+ *           e0
+ *            | (et)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll19)
+{
+	int efd[2];
+	int sfd[2];
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, sfd), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 0);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *           t0
+ *            | (ew)
+ *           e0
+ *            | (et)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll20)
+{
+	int efd[2];
+	int sfd[2];
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, sfd), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 0);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *          t0
+ *           | (p)
+ *          e0
+ *           | (lt)
+ *          e1
+ *           | (lt)
+ *          s0
+ */
+TEST(epoll21)
+{
+	int efd[2];
+	int sfd[2];
+	struct pollfd pfd;
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, sfd), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *          t0
+ *           | (p)
+ *          e0
+ *           | (lt)
+ *          e1
+ *           | (et)
+ *          s0
+ */
+TEST(epoll22)
+{
+	int efd[2];
+	int sfd[2];
+	struct pollfd pfd;
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, sfd), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *          t0
+ *           | (p)
+ *          e0
+ *           | (et)
+ *          e1
+ *           | (lt)
+ *          s0
+ */
+TEST(epoll23)
+{
+	int efd[2];
+	int sfd[2];
+	struct pollfd pfd;
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, sfd), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 0);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 0);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *          t0
+ *           | (p)
+ *          e0
+ *           | (et)
+ *          e1
+ *           | (et)
+ *          s0
+ */
+TEST(epoll24)
+{
+	int efd[2];
+	int sfd[2];
+	struct pollfd pfd;
+	struct epoll_event e;
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, sfd), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], &e), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 1);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 0);
+	EXPECT_EQ(epoll_wait(efd[0], &e, 1, 0), 0);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(sfd[0]);
+	close(sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (ew)
+ *           e0
+ *            | (lt)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll25)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (ew)
+ *           e0
+ *            | (lt)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll26)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (ew)
+ *           e0
+ *            | (et)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll27)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 1);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (ew)
+ *           e0
+ *            | (et)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll28)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 1);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (p)
+ *           e0
+ *            | (lt)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll29)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (p)
+ *           e0
+ *            | (lt)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll30)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (p)
+ *           e0
+ *            | (et)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll31)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 1);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (p)
+ *           e0
+ *            | (et)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll32)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 1);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *    (ew) |    | (ew)
+ *         |   e0
+ *          \  / (lt)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll33)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[1], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *    (ew) |    | (ew)
+ *         |   e0
+ *          \  / (lt)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll34)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1o, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[1], &e, 1, -1) > 0)
+		__sync_fetch_and_or(&ctx.count, 2);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_TRUE((ctx.count == 2) || (ctx.count == 3));
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *    (ew) |    | (ew)
+ *         |   e0
+ *          \  / (et)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll35)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[1], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *    (ew) |    | (ew)
+ *         |   e0
+ *          \  / (et)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll36)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1o, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[1], &e, 1, -1) > 0)
+		__sync_fetch_and_or(&ctx.count, 2);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_TRUE((ctx.count == 2) || (ctx.count == 3));
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *     (p) |    | (ew)
+ *         |   e0
+ *          \  / (lt)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll37)
+{
+	pthread_t emitter;
+	struct pollfd pfd;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	pfd.fd = ctx.efd[1];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx.efd[1], &e, 1, 0) > 0)
+			__sync_fetch_and_add(&ctx.count, 1);
+	}
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *     (p) |    | (ew)
+ *         |   e0
+ *          \  / (lt)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll38)
+{
+	pthread_t emitter;
+	struct pollfd pfd;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1o, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	pfd.fd = ctx.efd[1];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx.efd[1], &e, 1, 0) > 0)
+			__sync_fetch_and_or(&ctx.count, 2);
+	}
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_TRUE((ctx.count == 2) || (ctx.count == 3));
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *     (p) |    | (ew)
+ *         |   e0
+ *          \  / (et)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll39)
+{
+	pthread_t emitter;
+	struct pollfd pfd;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	pfd.fd = ctx.efd[1];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx.efd[1], &e, 1, 0) > 0)
+			__sync_fetch_and_add(&ctx.count, 1);
+	}
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *     (p) |    | (ew)
+ *         |   e0
+ *          \  / (et)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll40)
+{
+	pthread_t emitter;
+	struct pollfd pfd;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1o, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	pfd.fd = ctx.efd[1];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx.efd[1], &e, 1, 0) > 0)
+			__sync_fetch_and_or(&ctx.count, 2);
+	}
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_TRUE((ctx.count == 2) || (ctx.count == 3));
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *    (ew) |    | (p)
+ *         |   e0
+ *          \  / (lt)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll41)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[1], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *    (ew) |    | (p)
+ *         |   e0
+ *          \  / (lt)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll42)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1op, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[1], &e, 1, -1) > 0)
+		__sync_fetch_and_or(&ctx.count, 2);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_TRUE((ctx.count == 2) || (ctx.count == 3));
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *    (ew) |    | (p)
+ *         |   e0
+ *          \  / (et)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll43)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[1], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *    (ew) |    | (p)
+ *         |   e0
+ *          \  / (et)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll44)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1op, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[1], &e, 1, -1) > 0)
+		__sync_fetch_and_or(&ctx.count, 2);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_TRUE((ctx.count == 2) || (ctx.count == 3));
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *     (p) |    | (p)
+ *         |   e0
+ *          \  / (lt)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll45)
+{
+	pthread_t emitter;
+	struct pollfd pfd;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	pfd.fd = ctx.efd[1];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx.efd[1], &e, 1, 0) > 0)
+			__sync_fetch_and_add(&ctx.count, 1);
+	}
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *     (p) |    | (p)
+ *         |   e0
+ *          \  / (lt)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll46)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1op, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[1], &e, 1, -1) > 0)
+		__sync_fetch_and_or(&ctx.count, 2);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_TRUE((ctx.count == 2) || (ctx.count == 3));
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *     (p) |    | (p)
+ *         |   e0
+ *          \  / (et)
+ *           e1
+ *            | (lt)
+ *           s0
+ */
+TEST(epoll47)
+{
+	pthread_t emitter;
+	struct pollfd pfd;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	pfd.fd = ctx.efd[1];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx.efd[1], &e, 1, 0) > 0)
+			__sync_fetch_and_add(&ctx.count, 1);
+	}
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *        t0   t1
+ *     (p) |    | (p)
+ *         |   e0
+ *          \  / (et)
+ *           e1
+ *            | (et)
+ *           s0
+ */
+TEST(epoll48)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, ctx.sfd), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1op, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry1, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[1], &e, 1, -1) > 0)
+		__sync_fetch_and_or(&ctx.count, 2);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_TRUE((ctx.count == 2) || (ctx.count == 3));
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+}
+
+/*
+ *           t0
+ *            | (ew)
+ *           e0
+ *     (lt) /  \ (lt)
+ *        e1    e2
+ *    (lt) |     | (lt)
+ *        s0    s2
+ */
+TEST(epoll49)
+{
+	int efd[3];
+	int sfd[4];
+	struct epoll_event events[2];
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[2]), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	efd[2] = epoll_create(1);
+	ASSERT_GE(efd[2], 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[2], EPOLL_CTL_ADD, sfd[2], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[2], events), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+	ASSERT_EQ(write(sfd[3], "w", 1), 1);
+
+	EXPECT_EQ(epoll_wait(efd[0], events, 2, 0), 2);
+	EXPECT_EQ(epoll_wait(efd[0], events, 2, 0), 2);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(efd[2]);
+	close(sfd[0]);
+	close(sfd[1]);
+	close(sfd[2]);
+	close(sfd[3]);
+}
+
+/*
+ *           t0
+ *            | (ew)
+ *           e0
+ *     (et) /  \ (et)
+ *        e1    e2
+ *    (lt) |     | (lt)
+ *        s0    s2
+ */
+TEST(epoll50)
+{
+	int efd[3];
+	int sfd[4];
+	struct epoll_event events[2];
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[2]), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	efd[2] = epoll_create(1);
+	ASSERT_GE(efd[2], 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[2], EPOLL_CTL_ADD, sfd[2], events), 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], events), 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[2], events), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+	ASSERT_EQ(write(sfd[3], "w", 1), 1);
+
+	EXPECT_EQ(epoll_wait(efd[0], events, 2, 0), 2);
+	EXPECT_EQ(epoll_wait(efd[0], events, 2, 0), 0);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(efd[2]);
+	close(sfd[0]);
+	close(sfd[1]);
+	close(sfd[2]);
+	close(sfd[3]);
+}
+
+/*
+ *           t0
+ *            | (p)
+ *           e0
+ *     (lt) /  \ (lt)
+ *        e1    e2
+ *    (lt) |     | (lt)
+ *        s0    s2
+ */
+TEST(epoll51)
+{
+	int efd[3];
+	int sfd[4];
+	struct pollfd pfd;
+	struct epoll_event events[2];
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[2]), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	efd[2] = epoll_create(1);
+	ASSERT_GE(efd[2], 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[2], EPOLL_CTL_ADD, sfd[2], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[2], events), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+	ASSERT_EQ(write(sfd[3], "w", 1), 1);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], events, 2, 0), 2);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], events, 2, 0), 2);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(efd[2]);
+	close(sfd[0]);
+	close(sfd[1]);
+	close(sfd[2]);
+	close(sfd[3]);
+}
+
+/*
+ *           t0
+ *            | (p)
+ *           e0
+ *     (et) /  \ (et)
+ *        e1    e2
+ *    (lt) |     | (lt)
+ *        s0    s2
+ */
+TEST(epoll52)
+{
+	int efd[3];
+	int sfd[4];
+	struct pollfd pfd;
+	struct epoll_event events[2];
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &sfd[2]), 0);
+
+	efd[0] = epoll_create(1);
+	ASSERT_GE(efd[0], 0);
+
+	efd[1] = epoll_create(1);
+	ASSERT_GE(efd[1], 0);
+
+	efd[2] = epoll_create(1);
+	ASSERT_GE(efd[2], 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[1], EPOLL_CTL_ADD, sfd[0], events), 0);
+
+	events[0].events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(efd[2], EPOLL_CTL_ADD, sfd[2], events), 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[1], events), 0);
+
+	events[0].events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(efd[0], EPOLL_CTL_ADD, efd[2], events), 0);
+
+	ASSERT_EQ(write(sfd[1], "w", 1), 1);
+	ASSERT_EQ(write(sfd[3], "w", 1), 1);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 1);
+	EXPECT_EQ(epoll_wait(efd[0], events, 2, 0), 2);
+
+	pfd.fd = efd[0];
+	pfd.events = POLLIN;
+	EXPECT_EQ(poll(&pfd, 1, 0), 0);
+	EXPECT_EQ(epoll_wait(efd[0], events, 2, 0), 0);
+
+	close(efd[0]);
+	close(efd[1]);
+	close(efd[2]);
+	close(sfd[0]);
+	close(sfd[1]);
+	close(sfd[2]);
+	close(sfd[3]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (ew)
+ *           e0
+ *     (lt) /  \ (lt)
+ *        e1    e2
+ *    (lt) |     | (lt)
+ *        s0    s2
+ */
+TEST(epoll53)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[2]), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	ctx.efd[2] = epoll_create(1);
+	ASSERT_GE(ctx.efd[2], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[2], EPOLL_CTL_ADD, ctx.sfd[2], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[2], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry2, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.efd[2]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+	close(ctx.sfd[2]);
+	close(ctx.sfd[3]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (ew)
+ *           e0
+ *     (et) /  \ (et)
+ *        e1    e2
+ *    (lt) |     | (lt)
+ *        s0    s2
+ */
+TEST(epoll54)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[2]), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	ctx.efd[2] = epoll_create(1);
+	ASSERT_GE(ctx.efd[2], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[2], EPOLL_CTL_ADD, ctx.sfd[2], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[2], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1a, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry2, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.efd[2]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+	close(ctx.sfd[2]);
+	close(ctx.sfd[3]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (p)
+ *           e0
+ *     (lt) /  \ (lt)
+ *        e1    e2
+ *    (lt) |     | (lt)
+ *        s0    s2
+ */
+TEST(epoll55)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[2]), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	ctx.efd[2] = epoll_create(1);
+	ASSERT_GE(ctx.efd[2], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[2], EPOLL_CTL_ADD, ctx.sfd[2], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[2], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry2, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.efd[2]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+	close(ctx.sfd[2]);
+	close(ctx.sfd[3]);
+}
+
+/*
+ *        t0    t1
+ *     (ew) \  / (p)
+ *           e0
+ *     (et) /  \ (et)
+ *        e1    e2
+ *    (lt) |     | (lt)
+ *        s0    s2
+ */
+TEST(epoll56)
+{
+	pthread_t emitter;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[2]), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	ctx.efd[2] = epoll_create(1);
+	ASSERT_GE(ctx.efd[2], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[2], EPOLL_CTL_ADD, ctx.sfd[2], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[2], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry2, &ctx), 0);
+
+	if (epoll_wait(ctx.efd[0], &e, 1, -1) > 0)
+		__sync_fetch_and_add(&ctx.count, 1);
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.efd[2]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+	close(ctx.sfd[2]);
+	close(ctx.sfd[3]);
+}
+
+/*
+ *        t0    t1
+ *      (p) \  / (p)
+ *           e0
+ *     (lt) /  \ (lt)
+ *        e1    e2
+ *    (lt) |     | (lt)
+ *        s0    s2
+ */
+TEST(epoll57)
+{
+	pthread_t emitter;
+	struct pollfd pfd;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[2]), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	ctx.efd[2] = epoll_create(1);
+	ASSERT_GE(ctx.efd[2], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[2], EPOLL_CTL_ADD, ctx.sfd[2], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[2], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry2, &ctx), 0);
+
+	pfd.fd = ctx.efd[0];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx.efd[0], &e, 1, 0) > 0)
+			__sync_fetch_and_add(&ctx.count, 1);
+	}
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.efd[2]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+	close(ctx.sfd[2]);
+	close(ctx.sfd[3]);
+}
+
+/*
+ *        t0    t1
+ *      (p) \  / (p)
+ *           e0
+ *     (et) /  \ (et)
+ *        e1    e2
+ *    (lt) |     | (lt)
+ *        s0    s2
+ */
+TEST(epoll58)
+{
+	pthread_t emitter;
+	struct pollfd pfd;
+	struct epoll_event e;
+	struct epoll_mtcontext ctx = { 0 };
+
+	signal(SIGUSR1, signal_handler);
+
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[0]), 0);
+	ASSERT_EQ(socketpair(AF_UNIX, SOCK_STREAM, 0, &ctx.sfd[2]), 0);
+
+	ctx.efd[0] = epoll_create(1);
+	ASSERT_GE(ctx.efd[0], 0);
+
+	ctx.efd[1] = epoll_create(1);
+	ASSERT_GE(ctx.efd[1], 0);
+
+	ctx.efd[2] = epoll_create(1);
+	ASSERT_GE(ctx.efd[2], 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[1], EPOLL_CTL_ADD, ctx.sfd[0], &e), 0);
+
+	e.events = EPOLLIN;
+	ASSERT_EQ(epoll_ctl(ctx.efd[2], EPOLL_CTL_ADD, ctx.sfd[2], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[1], &e), 0);
+
+	e.events = EPOLLIN | EPOLLET;
+	ASSERT_EQ(epoll_ctl(ctx.efd[0], EPOLL_CTL_ADD, ctx.efd[2], &e), 0);
+
+	ctx.main = pthread_self();
+	ASSERT_EQ(pthread_create(&ctx.waiter, NULL, waiter_entry1ap, &ctx), 0);
+	ASSERT_EQ(pthread_create(&emitter, NULL, emitter_entry2, &ctx), 0);
+
+	pfd.fd = ctx.efd[0];
+	pfd.events = POLLIN;
+	if (poll(&pfd, 1, -1) > 0) {
+		if (epoll_wait(ctx.efd[0], &e, 1, 0) > 0)
+			__sync_fetch_and_add(&ctx.count, 1);
+	}
+
+	ASSERT_EQ(pthread_join(ctx.waiter, NULL), 0);
+	EXPECT_EQ(ctx.count, 2);
+
+	if (pthread_tryjoin_np(emitter, NULL) < 0) {
+		pthread_kill(emitter, SIGUSR1);
+		pthread_join(emitter, NULL);
+	}
+
+	close(ctx.efd[0]);
+	close(ctx.efd[1]);
+	close(ctx.efd[2]);
+	close(ctx.sfd[0]);
+	close(ctx.sfd[1]);
+	close(ctx.sfd[2]);
+	close(ctx.sfd[3]);
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/vm/config b/tools/testing/selftests/vm/config
index 1c0d76cb5adf..93b90a9b1eeb 100644
--- a/tools/testing/selftests/vm/config
+++ b/tools/testing/selftests/vm/config
@@ -1,2 +1,3 @@
 CONFIG_SYSVIPC=y
 CONFIG_USERFAULTFD=y
+CONFIG_TEST_VMALLOC=m
diff --git a/tools/testing/selftests/vm/gup_benchmark.c b/tools/testing/selftests/vm/gup_benchmark.c
index cb3fc09645c4..485cf06ef013 100644
--- a/tools/testing/selftests/vm/gup_benchmark.c
+++ b/tools/testing/selftests/vm/gup_benchmark.c
@@ -71,7 +71,7 @@ int main(int argc, char **argv)
 			flags |= MAP_SHARED;
 			break;
 		case 'H':
-			flags |= MAP_HUGETLB;
+			flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
 			break;
 		default:
 			return -1;