Merge tag 's390-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add support for stackleak feature. Also allow specifying
   architecture-specific stackleak poison function to enable faster
   implementation. On s390, the mvc-based implementation helps decrease
   typical overhead from a factor of 3 to just 25%

 - Convert all assembler files to use SYM* style macros, deprecating the
   ENTRY() macro and other annotations. Select ARCH_USE_SYM_ANNOTATIONS

 - Improve KASLR to also randomize module and special amode31 code base
   load addresses

 - Rework decompressor memory tracking to support memory holes and
   improve error handling

 - Add support for protected virtualization AP binding

 - Add support for set_direct_map() calls

 - Implement set_memory_rox() and noexec module_alloc()

 - Remove obsolete overriding of mem*() functions for KASAN

 - Rework kexec/kdump to avoid using nodat_stack to call purgatory

 - Convert the rest of the s390 code to use flexible-array member
   instead of a zero-length array

 - Clean up uaccess inline asm

 - Enable ARCH_HAS_MEMBARRIER_SYNC_CORE

 - Convert to using CONFIG_FUNCTION_ALIGNMENT and enable
   DEBUG_FORCE_FUNCTION_ALIGN_64B

 - Resolve last_break in userspace fault reports

 - Simplify one-level sysctl registration

 - Clean up branch prediction handling

 - Rework CPU counter facility to retrieve available counter sets just
   once

 - Other various small fixes and improvements all over the code

* tag 's390-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (118 commits)
  s390/stackleak: provide fast __stackleak_poison() implementation
  stackleak: allow to specify arch specific stackleak poison function
  s390: select ARCH_USE_SYM_ANNOTATIONS
  s390/mm: use VM_FLUSH_RESET_PERMS in module_alloc()
  s390: wire up memfd_secret system call
  s390/mm: enable ARCH_HAS_SET_DIRECT_MAP
  s390/mm: use BIT macro to generate SET_MEMORY bit masks
  s390/relocate_kernel: adjust indentation
  s390/relocate_kernel: use SYM* macros instead of ENTRY(), etc.
  s390/entry: use SYM* macros instead of ENTRY(), etc.
  s390/purgatory: use SYM* macros instead of ENTRY(), etc.
  s390/kprobes: use SYM* macros instead of ENTRY(), etc.
  s390/reipl: use SYM* macros instead of ENTRY(), etc.
  s390/head64: use SYM* macros instead of ENTRY(), etc.
  s390/earlypgm: use SYM* macros instead of ENTRY(), etc.
  s390/mcount: use SYM* macros instead of ENTRY(), etc.
  s390/crc32le: use SYM* macros instead of ENTRY(), etc.
  s390/crc32be: use SYM* macros instead of ENTRY(), etc.
  s390/crypto,chacha: use SYM* macros instead of ENTRY(), etc.
  s390/amode31: use SYM* macros instead of ENTRY(), etc.
  ...

1 files changed, 42 insertions, 4 deletions

diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index e98d9650764b..dc17896a001a 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -99,7 +99,6 @@ void cpu_detect_mhz_feature(void);
 
 extern const struct seq_operations cpuinfo_op;
 extern void execve_tail(void);
-extern void __bpon(void);
 unsigned long vdso_size(void);
 
 /*
@@ -119,6 +118,41 @@ unsigned long vdso_size(void);
 
 #define HAVE_ARCH_PICK_MMAP_LAYOUT
 
+#define __stackleak_poison __stackleak_poison
+static __always_inline void __stackleak_poison(unsigned long erase_low,
+					       unsigned long erase_high,
+					       unsigned long poison)
+{
+	unsigned long tmp, count;
+
+	count = erase_high - erase_low;
+	if (!count)
+		return;
+	asm volatile(
+		"	cghi	%[count],8\n"
+		"	je	2f\n"
+		"	aghi	%[count],-(8+1)\n"
+		"	srlg	%[tmp],%[count],8\n"
+		"	ltgr	%[tmp],%[tmp]\n"
+		"	jz	1f\n"
+		"0:	stg	%[poison],0(%[addr])\n"
+		"	mvc	8(256-8,%[addr]),0(%[addr])\n"
+		"	la	%[addr],256(%[addr])\n"
+		"	brctg	%[tmp],0b\n"
+		"1:	stg	%[poison],0(%[addr])\n"
+		"	larl	%[tmp],3f\n"
+		"	ex	%[count],0(%[tmp])\n"
+		"	j	4f\n"
+		"2:	stg	%[poison],0(%[addr])\n"
+		"	j	4f\n"
+		"3:	mvc	8(1,%[addr]),0(%[addr])\n"
+		"4:\n"
+		: [addr] "+&a" (erase_low), [count] "+&d" (count), [tmp] "=&a" (tmp)
+		: [poison] "d" (poison)
+		: "memory", "cc"
+		);
+}
+
 /*
  * Thread structure
  */
@@ -227,6 +261,13 @@ static __always_inline unsigned long __current_stack_pointer(void)
 	return sp;
 }
 
+static __always_inline bool on_thread_stack(void)
+{
+	unsigned long ksp = S390_lowcore.kernel_stack;
+
+	return !((ksp ^ current_stack_pointer) & ~(THREAD_SIZE - 1));
+}
+
 static __always_inline unsigned short stap(void)
 {
 	unsigned short cpu_address;
@@ -329,9 +370,6 @@ static __always_inline void __noreturn disabled_wait(void)
 
 #define ARCH_LOW_ADDRESS_LIMIT	0x7fffffffUL
 
-extern int s390_isolate_bp(void);
-extern int s390_isolate_bp_guest(void);
-
 static __always_inline bool regs_irqs_disabled(struct pt_regs *regs)
 {
 	return arch_irqs_disabled_flags(regs->psw.mask);