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Diffstat (limited to 'arch/powerpc/mm/book3s64/hash_utils.c')
-rw-r--r--arch/powerpc/mm/book3s64/hash_utils.c50
1 files changed, 39 insertions, 11 deletions
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c
index 468169e33c86..1478fceeb683 100644
--- a/arch/powerpc/mm/book3s64/hash_utils.c
+++ b/arch/powerpc/mm/book3s64/hash_utils.c
@@ -232,8 +232,6 @@ unsigned long htab_convert_pte_flags(unsigned long pteflags)
rflags |= HPTE_R_I;
else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_NON_IDEMPOTENT)
rflags |= (HPTE_R_I | HPTE_R_G);
- else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_SAO)
- rflags |= (HPTE_R_W | HPTE_R_I | HPTE_R_M);
else
/*
* Add memory coherence if cache inhibited is not set
@@ -596,7 +594,7 @@ static void __init htab_scan_page_sizes(void)
}
#ifdef CONFIG_HUGETLB_PAGE
- if (!hugetlb_disabled) {
+ if (!hugetlb_disabled && !early_radix_enabled() ) {
/* Reserve 16G huge page memory sections for huge pages */
of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL);
}
@@ -663,11 +661,10 @@ static void __init htab_init_page_sizes(void)
* Pick a size for the linear mapping. Currently, we only
* support 16M, 1M and 4K which is the default
*/
- if (IS_ENABLED(STRICT_KERNEL_RWX) &&
+ if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) &&
(unsigned long)_stext % 0x1000000) {
if (mmu_psize_defs[MMU_PAGE_16M].shift)
- pr_warn("Kernel not 16M aligned, "
- "disabling 16M linear map alignment");
+ pr_warn("Kernel not 16M aligned, disabling 16M linear map alignment\n");
aligned = false;
}
@@ -788,7 +785,7 @@ static unsigned long __init htab_get_table_size(void)
}
#ifdef CONFIG_MEMORY_HOTPLUG
-int resize_hpt_for_hotplug(unsigned long new_mem_size)
+static int resize_hpt_for_hotplug(unsigned long new_mem_size)
{
unsigned target_hpt_shift;
@@ -822,6 +819,8 @@ int hash__create_section_mapping(unsigned long start, unsigned long end,
return -1;
}
+ resize_hpt_for_hotplug(memblock_phys_mem_size());
+
rc = htab_bolt_mapping(start, end, __pa(start),
pgprot_val(prot), mmu_linear_psize,
mmu_kernel_ssize);
@@ -839,6 +838,10 @@ int hash__remove_section_mapping(unsigned long start, unsigned long end)
int rc = htab_remove_mapping(start, end, mmu_linear_psize,
mmu_kernel_ssize);
WARN_ON(rc < 0);
+
+ if (resize_hpt_for_hotplug(memblock_phys_mem_size()) == -ENOSPC)
+ pr_warn("Hash collision while resizing HPT\n");
+
return rc;
}
#endif /* CONFIG_MEMORY_HOTPLUG */
@@ -1111,6 +1114,10 @@ void hash__early_init_mmu_secondary(void)
if (cpu_has_feature(CPU_FTR_ARCH_206)
&& cpu_has_feature(CPU_FTR_HVMODE))
tlbiel_all();
+
+#ifdef CONFIG_PPC_MEM_KEYS
+ mtspr(SPRN_UAMOR, default_uamor);
+#endif
}
#endif /* CONFIG_SMP */
@@ -1559,6 +1566,7 @@ static void hash_preload(struct mm_struct *mm, pte_t *ptep, unsigned long ea,
pgd_t *pgdir;
int rc, ssize, update_flags = 0;
unsigned long access = _PAGE_PRESENT | _PAGE_READ | (is_exec ? _PAGE_EXEC : 0);
+ unsigned long flags;
BUG_ON(get_region_id(ea) != USER_REGION_ID);
@@ -1592,6 +1600,28 @@ static void hash_preload(struct mm_struct *mm, pte_t *ptep, unsigned long ea,
return;
#endif /* CONFIG_PPC_64K_PAGES */
+ /*
+ * __hash_page_* must run with interrupts off, as it sets the
+ * H_PAGE_BUSY bit. It's possible for perf interrupts to hit at any
+ * time and may take a hash fault reading the user stack, see
+ * read_user_stack_slow() in the powerpc/perf code.
+ *
+ * If that takes a hash fault on the same page as we lock here, it
+ * will bail out when seeing H_PAGE_BUSY set, and retry the access
+ * leading to an infinite loop.
+ *
+ * Disabling interrupts here does not prevent perf interrupts, but it
+ * will prevent them taking hash faults (see the NMI test in
+ * do_hash_page), then read_user_stack's copy_from_user_nofault will
+ * fail and perf will fall back to read_user_stack_slow(), which
+ * walks the Linux page tables.
+ *
+ * Interrupts must also be off for the duration of the
+ * mm_is_thread_local test and update, to prevent preempt running the
+ * mm on another CPU (XXX: this may be racy vs kthread_use_mm).
+ */
+ local_irq_save(flags);
+
/* Is that local to this CPU ? */
if (mm_is_thread_local(mm))
update_flags |= HPTE_LOCAL_UPDATE;
@@ -1614,6 +1644,8 @@ static void hash_preload(struct mm_struct *mm, pte_t *ptep, unsigned long ea,
mm_ctx_user_psize(&mm->context),
mm_ctx_user_psize(&mm->context),
pte_val(*ptep));
+
+ local_irq_restore(flags);
}
/*
@@ -1706,10 +1738,6 @@ unsigned long pte_get_hash_gslot(unsigned long vpn, unsigned long shift,
return gslot;
}
-/*
- * WARNING: This is called from hash_low_64.S, if you change this prototype,
- * do not forget to update the assembly call site !
- */
void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize, int ssize,
unsigned long flags)
{