The patch titled Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: Jane Chu jane.chu@oracle.com Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison Date: Tue, 16 Dec 2025 14:56:21 -0700

When a newly poisoned subpage ends up in an already poisoned hugetlb folio, 'num_poisoned_pages' is incremented, but the per node ->mf_stats is not. Fix the inconsistency by designating action_result() to update them both.

Link: https://lkml.kernel.org/r/20251216215621.920093-1-jane.chu@oracle.com Fixes: 18f41fa616ee4 ("mm: memory-failure: bump memory failure stats to pglist_data") Signed-off-by: Jane Chu jane.chu@oracle.com Cc: David Rientjes rientjes@google.com Cc: Jiaqi Yan jiaqiyan@google.com Cc: Liam Howlett liam.howlett@oracle.com Cc: Lorenzo Stoakes lorenzo.stoakes@oracle.com Cc: Miaohe Lin linmiaohe@huawei.com Cc: Michal Hocko mhocko@suse.com Cc: Mike Rapoport rppt@kernel.org Cc: Muchun Song muchun.song@linux.dev Cc: Oscar Salvador osalvador@suse.de Cc: Suren Baghdasaryan surenb@google.com Cc: William Roche william.roche@oracle.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

include/linux/hugetlb.h | 4 ++-- include/linux/mm.h | 4 ++-- mm/hugetlb.c | 4 ++-- mm/memory-failure.c | 22 +++++++++++++--------- 4 files changed, 19 insertions(+), 15 deletions(-)

--- a/include/linux/hugetlb.h~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison +++ a/include/linux/hugetlb.h @@ -156,7 +156,7 @@ long hugetlb_unreserve_pages(struct inod bool folio_isolate_hugetlb(struct folio *folio, struct list_head *list); int get_hwpoison_hugetlb_folio(struct folio *folio, bool *hugetlb, bool unpoison); int get_huge_page_for_hwpoison(unsigned long pfn, int flags, - bool *migratable_cleared); + bool *migratable_cleared, bool *samepg); void folio_putback_hugetlb(struct folio *folio); void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio, int reason); void hugetlb_fix_reserve_counts(struct inode *inode); @@ -418,7 +418,7 @@ static inline int get_hwpoison_hugetlb_f }

static inline int get_huge_page_for_hwpoison(unsigned long pfn, int flags, - bool *migratable_cleared) + bool *migratable_cleared, bool *samepg) { return 0; } --- a/include/linux/mm.h~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison +++ a/include/linux/mm.h @@ -4351,7 +4351,7 @@ extern int soft_offline_page(unsigned lo extern const struct attribute_group memory_failure_attr_group; extern void memory_failure_queue(unsigned long pfn, int flags); extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags, - bool *migratable_cleared); + bool *migratable_cleared, bool *samepg); void num_poisoned_pages_inc(unsigned long pfn); void num_poisoned_pages_sub(unsigned long pfn, long i); #else @@ -4360,7 +4360,7 @@ static inline void memory_failure_queue( }

static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags, - bool *migratable_cleared) + bool *migratable_cleared, bool *samepg) { return 0; } --- a/mm/hugetlb.c~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison +++ a/mm/hugetlb.c @@ -7132,12 +7132,12 @@ int get_hwpoison_hugetlb_folio(struct fo }

int get_huge_page_for_hwpoison(unsigned long pfn, int flags, - bool *migratable_cleared) + bool *migratable_cleared, bool *samepg) { int ret;

spin_lock_irq(&hugetlb_lock); - ret = __get_huge_page_for_hwpoison(pfn, flags, migratable_cleared); + ret = __get_huge_page_for_hwpoison(pfn, flags, migratable_cleared, samepg); spin_unlock_irq(&hugetlb_lock); return ret; } --- a/mm/memory-failure.c~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison +++ a/mm/memory-failure.c @@ -1883,7 +1883,8 @@ static unsigned long __folio_free_raw_hw return count; }

-static int folio_set_hugetlb_hwpoison(struct folio *folio, struct page *page) +static int folio_set_hugetlb_hwpoison(struct folio *folio, struct page *page, + bool *samepg) { struct llist_head *head; struct raw_hwp_page *raw_hwp; @@ -1899,17 +1900,16 @@ static int folio_set_hugetlb_hwpoison(st return -EHWPOISON; head = raw_hwp_list_head(folio); llist_for_each_entry(p, head->first, node) { - if (p->page == page) + if (p->page == page) { + *samepg = true; return -EHWPOISON; + } }

raw_hwp = kmalloc(sizeof(struct raw_hwp_page), GFP_ATOMIC); if (raw_hwp) { raw_hwp->page = page; llist_add(&raw_hwp->node, head); - /* the first error event will be counted in action_result(). */ - if (ret) - num_poisoned_pages_inc(page_to_pfn(page)); } else { /* * Failed to save raw error info. We no longer trace all @@ -1966,7 +1966,7 @@ void folio_clear_hugetlb_hwpoison(struct * -EHWPOISON - the hugepage is already hwpoisoned */ int __get_huge_page_for_hwpoison(unsigned long pfn, int flags, - bool *migratable_cleared) + bool *migratable_cleared, bool *samepg) { struct page *page = pfn_to_page(pfn); struct folio *folio = page_folio(page); @@ -1991,7 +1991,7 @@ int __get_huge_page_for_hwpoison(unsigne goto out; }

- if (folio_set_hugetlb_hwpoison(folio, page)) { + if (folio_set_hugetlb_hwpoison(folio, page, samepg)) { ret = -EHWPOISON; goto out; } @@ -2024,11 +2024,12 @@ static int try_memory_failure_hugetlb(un struct page *p = pfn_to_page(pfn); struct folio *folio; unsigned long page_flags; + bool samepg = false; bool migratable_cleared = false;

*hugetlb = 1; retry: - res = get_huge_page_for_hwpoison(pfn, flags, &migratable_cleared); + res = get_huge_page_for_hwpoison(pfn, flags, &migratable_cleared, &samepg); if (res == 2) { /* fallback to normal page handling */ *hugetlb = 0; return 0; @@ -2037,7 +2038,10 @@ retry: folio = page_folio(p); res = kill_accessing_process(current, folio_pfn(folio), flags); } - action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED); + if (samepg) + action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED); + else + action_result(pfn, MF_MSG_HUGE, MF_FAILED); return res; } else if (res == -EBUSY) { if (!(flags & MF_NO_RETRY)) { _

Patches currently in -mm which might be from jane.chu@oracle.com are

mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch