From 0792a4a6195a6d67a4ead2554da393cbd8dcdf5a Mon Sep 17 00:00:00 2001 From: Miaohe Lin Date: Thu, 18 Aug 2022 21:00:15 +0800 Subject: [PATCH] mm, hwpoison: kill procs if unmap fails If try_to_unmap() fails, the hwpoisoned page still resides in the address space of some processes. We should kill these processes or the hwpoisoned page might be consumed later. collect_procs() is always called to collect relevant processes now so they can be killed later if unmap fails. [linmiaohe@huawei.com: v2] Link: https://lkml.kernel.org/r/20220823032346.4260-6-linmiaohe@huawei.com Link: https://lkml.kernel.org/r/20220818130016.45313-6-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Acked-by: Naoya Horiguchi Signed-off-by: Andrew Morton --- mm/memory-failure.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 208a0f85ef54..3b8e7937ce75 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1397,7 +1397,7 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, struct address_space *mapping; LIST_HEAD(tokill); bool unmap_success; - int kill = 1, forcekill; + int forcekill; bool mlocked = PageMlocked(hpage); /* @@ -1438,7 +1438,6 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, if (page_mkclean(hpage)) { SetPageDirty(hpage); } else { - kill = 0; ttu |= TTU_IGNORE_HWPOISON; pr_info("%#lx: corrupted page was clean: dropped without side effects\n", pfn); @@ -1449,12 +1448,8 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, * First collect all the processes that have the page * mapped in dirty form. This has to be done before try_to_unmap, * because ttu takes the rmap data structures down. - * - * Error handling: We ignore errors here because - * there's nothing that can be done. */ - if (kill) - collect_procs(hpage, &tokill, flags & MF_ACTION_REQUIRED); + collect_procs(hpage, &tokill, flags & MF_ACTION_REQUIRED); if (PageHuge(hpage) && !PageAnon(hpage)) { /* @@ -1496,7 +1491,8 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, * use a more force-full uncatchable kill to prevent * any accesses to the poisoned memory. */ - forcekill = PageDirty(hpage) || (flags & MF_MUST_KILL); + forcekill = PageDirty(hpage) || (flags & MF_MUST_KILL) || + !unmap_success; kill_procs(&tokill, forcekill, !unmap_success, pfn, flags); return unmap_success; -- GitLab