From: Naoya Horiguchi <naoya.horiguchi@xxxxxxx> Currently PageHWPoison flag does not behave well when experiencing memory hotremove/hotplug. Any data field in struct page is unreliable when the associated memory is offlined, and the current mechanism can't tell whether a memory block is onlined because a new memory devices is installed or because previous failed offline operations are undone. Especially if there's a hwpoisoned memory, it's unclear what the best option is. So introduce a new mechanism to make struct memory_block remember that a memory block has hwpoisoned memory inside it. And make any online event fail if the onlining memory block contains hwpoison. struct memory_block is freed and reallocated over ACPI-based hotremove/hotplug, but not over sysfs-based hotremove/hotplug. So the new counter can distinguish these cases. Signed-off-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx> Reported-by: kernel test robot <lkp@xxxxxxxxx> --- ChangeLog v5 -> v6: - fix build errors over memblk_nr_poison_inc() and memblk_nr_poison_sub(), - pass "struct memory_block *" to memblk_nr_poison() instead of pfn, - removed clear_hwpoisoned_pages() and call num_poisoned_pages_sub() directly. - add static keyword to the definition of memblk_nr_poison(). - Mioahe added Reviewed-by for v5, but I have some non trivial changes in v6, so let me hold to add it. - unpoison_memory() properly cancels per-memblk hwpoison counter. ChangeLog v4 -> v5: - add Reported-by of lkp bot, - check both CONFIG_MEMORY_FAILURE and CONFIG_MEMORY_HOTPLUG in introduced #ifdefs, intending to fix "undefined reference" errors in aarch64. ChangeLog v3 -> v4: - fix build error (https://lore.kernel.org/linux-mm/202209231134.tnhKHRfg-lkp@xxxxxxxxx/) by using memblk_nr_poison() to access to the member ->nr_hwpoison --- drivers/base/memory.c | 40 ++++++++++++++++++++++++++++++++++++++++ include/linux/memory.h | 3 +++ include/linux/mm.h | 18 ++++++++++++++++++ mm/internal.h | 8 -------- mm/memory-failure.c | 36 +++++++++++------------------------- mm/sparse.c | 2 -- 6 files changed, 72 insertions(+), 35 deletions(-) diff --git a/drivers/base/memory.c b/drivers/base/memory.c index 9aa0da991cfb..5d00d8a14c79 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -175,6 +175,17 @@ int memory_notify(unsigned long val, void *v) return blocking_notifier_call_chain(&memory_chain, val, v); } +#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG) +void memblk_nr_poison_inc(unsigned long pfn); +void memblk_nr_poison_sub(unsigned long pfn, long i); +static unsigned long memblk_nr_poison(struct memory_block *mem); +#else +static inline unsigned long memblk_nr_poison(struct memory_block *mem) +{ + return 0; +} +#endif + static int memory_block_online(struct memory_block *mem) { unsigned long start_pfn = section_nr_to_pfn(mem->start_section_nr); @@ -183,6 +194,9 @@ static int memory_block_online(struct memory_block *mem) struct zone *zone; int ret; + if (memblk_nr_poison(mem)) + return -EHWPOISON; + zone = zone_for_pfn_range(mem->online_type, mem->nid, mem->group, start_pfn, nr_pages); @@ -864,6 +878,7 @@ void remove_memory_block_devices(unsigned long start, unsigned long size) mem = find_memory_block_by_id(block_id); if (WARN_ON_ONCE(!mem)) continue; + num_poisoned_pages_sub(-1UL, memblk_nr_poison(mem)); unregister_memory_block_under_nodes(mem); remove_memory_block(mem); } @@ -1164,3 +1179,28 @@ int walk_dynamic_memory_groups(int nid, walk_memory_groups_func_t func, } return ret; } + +#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG) +void memblk_nr_poison_inc(unsigned long pfn) +{ + const unsigned long block_id = pfn_to_block_id(pfn); + struct memory_block *mem = find_memory_block_by_id(block_id); + + if (mem) + atomic_long_inc(&mem->nr_hwpoison); +} + +void memblk_nr_poison_sub(unsigned long pfn, long i) +{ + const unsigned long block_id = pfn_to_block_id(pfn); + struct memory_block *mem = find_memory_block_by_id(block_id); + + if (mem) + atomic_long_sub(i, &mem->nr_hwpoison); +} + +static unsigned long memblk_nr_poison(struct memory_block *mem) +{ + return atomic_long_read(&mem->nr_hwpoison); +} +#endif diff --git a/include/linux/memory.h b/include/linux/memory.h index aa619464a1df..ad8cd9bb3239 100644 --- a/include/linux/memory.h +++ b/include/linux/memory.h @@ -85,6 +85,9 @@ struct memory_block { unsigned long nr_vmemmap_pages; struct memory_group *group; /* group (if any) for this block */ struct list_head group_next; /* next block inside memory group */ +#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG) + atomic_long_t nr_hwpoison; +#endif }; int arch_get_memory_phys_device(unsigned long start_pfn); diff --git a/include/linux/mm.h b/include/linux/mm.h index 17119dbf8fad..f80269e90772 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3280,6 +3280,7 @@ extern int soft_offline_page(unsigned long pfn, int flags); extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags, bool *migratable_cleared); extern void num_poisoned_pages_inc(unsigned long pfn); +extern void num_poisoned_pages_sub(unsigned long pfn, long i); #else static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags, bool *migratable_cleared) @@ -3290,6 +3291,23 @@ static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags, static inline void num_poisoned_pages_inc(unsigned long pfn) { } + +static inline void num_poisoned_pages_sub(unsigned long pfn, long i) +{ +} +#endif + +#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG) +extern void memblk_nr_poison_inc(unsigned long pfn); +extern void memblk_nr_poison_sub(unsigned long pfn, long i); +#else +static inline void memblk_nr_poison_inc(unsigned long pfn) +{ +} + +static inline void memblk_nr_poison_sub(unsigned long pfn, long i) +{ +} #endif #ifndef arch_memory_failure diff --git a/mm/internal.h b/mm/internal.h index b3002e03c28f..42ba8b96cab5 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -708,14 +708,6 @@ extern u64 hwpoison_filter_flags_value; extern u64 hwpoison_filter_memcg; extern u32 hwpoison_filter_enable; -#ifdef CONFIG_MEMORY_FAILURE -void clear_hwpoisoned_pages(struct page *memmap, int nr_pages); -#else -static inline void clear_hwpoisoned_pages(struct page *memmap, int nr_pages) -{ -} -#endif - extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long); diff --git a/mm/memory-failure.c b/mm/memory-failure.c index c19a301f16fc..4f5921590b76 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -77,11 +77,14 @@ static bool hw_memory_failure __read_mostly = false; inline void num_poisoned_pages_inc(unsigned long pfn) { atomic_long_inc(&num_poisoned_pages); + memblk_nr_poison_inc(pfn); } -static inline void num_poisoned_pages_sub(unsigned long pfn, long i) +inline void num_poisoned_pages_sub(unsigned long pfn, long i) { atomic_long_sub(i, &num_poisoned_pages); + if (pfn != -1UL) + memblk_nr_poison_sub(pfn, i); } /* @@ -1706,6 +1709,8 @@ static unsigned long __free_raw_hwp_pages(struct page *hpage, bool move_flag) if (move_flag) SetPageHWPoison(p->page); + else + num_poisoned_pages_sub(page_to_pfn(p->page), 1); kfree(p); count++; } @@ -2337,6 +2342,7 @@ int unpoison_memory(unsigned long pfn) int ret = -EBUSY; int freeit = 0; unsigned long count = 1; + bool huge = false; static DEFINE_RATELIMIT_STATE(unpoison_rs, DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); @@ -2385,6 +2391,7 @@ int unpoison_memory(unsigned long pfn) ret = get_hwpoison_page(p, MF_UNPOISON); if (!ret) { if (PageHuge(p)) { + huge = true; count = free_raw_hwp_pages(page, false); if (count == 0) { ret = -EBUSY; @@ -2400,6 +2407,7 @@ int unpoison_memory(unsigned long pfn) pfn, &unpoison_rs); } else { if (PageHuge(p)) { + huge = true; count = free_raw_hwp_pages(page, false); if (count == 0) { ret = -EBUSY; @@ -2419,7 +2427,8 @@ int unpoison_memory(unsigned long pfn) unlock_mutex: mutex_unlock(&mf_mutex); if (!ret || freeit) { - num_poisoned_pages_sub(pfn, count); + if (!huge) + num_poisoned_pages_sub(pfn, 1); unpoison_pr_info("Unpoison: Software-unpoisoned page %#lx\n", page_to_pfn(p), &unpoison_rs); } @@ -2622,26 +2631,3 @@ int soft_offline_page(unsigned long pfn, int flags) return ret; } - -void clear_hwpoisoned_pages(struct page *memmap, int nr_pages) -{ - int i, total = 0; - - /* - * A further optimization is to have per section refcounted - * num_poisoned_pages. But that would need more space per memmap, so - * for now just do a quick global check to speed up this routine in the - * absence of bad pages. - */ - if (atomic_long_read(&num_poisoned_pages) == 0) - return; - - for (i = 0; i < nr_pages; i++) { - if (PageHWPoison(&memmap[i])) { - total++; - ClearPageHWPoison(&memmap[i]); - } - } - if (total) - num_poisoned_pages_sub(0, total); -} diff --git a/mm/sparse.c b/mm/sparse.c index e5a8a3a0edd7..2779b419ef2a 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -926,8 +926,6 @@ void sparse_remove_section(struct mem_section *ms, unsigned long pfn, unsigned long nr_pages, unsigned long map_offset, struct vmem_altmap *altmap) { - clear_hwpoisoned_pages(pfn_to_page(pfn) + map_offset, - nr_pages - map_offset); section_deactivate(pfn, nr_pages, altmap); } #endif /* CONFIG_MEMORY_HOTPLUG */ -- 2.25.1
