When a hugetlb folio is being poisoned again, try_memory_failure_hugetlb() passed head pfn to kill_accessing_process(), that is not right. The precise pfn of the poisoned page should be used in order to determine the precise vaddr as the SIGBUS payload. This issue has already been taken care of in the normal path, that is, hwpoison_user_mappings(), see [1][2]. Further more, for [3] to work correctly in the hugetlb repoisoning case, it's essential to inform VM the precise poisoned page, not the head page. [1] https://lkml.kernel.org/r/20231218135837.3310403-1-willy@infradead.org [2] https://lkml.kernel.org/r/20250224211445.2663312-1-jane.chu@oracle.com [3] https://lore.kernel.org/lkml/20251116013223.1557158-1-jiaqiyan@google.com/ Cc: Signed-off-by: Jane Chu Reviewed-by: Liam R. Howlett Acked-by: Miaohe Lin --- v6 -> v7: No change. v5 -> v6: comment from Miaohe, add an acked-by. v5, v4: No change. v2 -> v3: incorporated suggestions from Miaohe and Matthew. v1 -> v2: pickup R-B, add stable to cc list. --- mm/memory-failure.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 473204359e1f..cf0d526e6d41 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -692,6 +692,8 @@ static int check_hwpoisoned_entry(pte_t pte, unsigned long addr, short shift, unsigned long poisoned_pfn, struct to_kill *tk) { unsigned long pfn = 0; + unsigned long hwpoison_vaddr; + unsigned long mask; if (pte_present(pte)) { pfn = pte_pfn(pte); @@ -702,10 +704,12 @@ static int check_hwpoisoned_entry(pte_t pte, unsigned long addr, short shift, pfn = softleaf_to_pfn(entry); } - if (!pfn || pfn != poisoned_pfn) + mask = ~((1UL << (shift - PAGE_SHIFT)) - 1); + if (!pfn || pfn != (poisoned_pfn & mask)) return 0; - set_to_kill(tk, addr, shift); + hwpoison_vaddr = addr + ((poisoned_pfn - pfn) << PAGE_SHIFT); + set_to_kill(tk, hwpoison_vaddr, shift); return 1; } @@ -2052,10 +2056,8 @@ static int try_memory_failure_hugetlb(unsigned long pfn, int flags, int *hugetlb case MF_HUGETLB_FOLIO_PRE_POISONED: case MF_HUGETLB_PAGE_PRE_POISONED: rv = -EHWPOISON; - if (flags & MF_ACTION_REQUIRED) { - folio = page_folio(p); - rv = kill_accessing_process(current, folio_pfn(folio), flags); - } + if (flags & MF_ACTION_REQUIRED) + rv = kill_accessing_process(current, pfn, flags); if (res == MF_HUGETLB_PAGE_PRE_POISONED) action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED); else -- 2.43.5