From: Yang Shi Date: Thu, 28 Oct 2021 21:36:07 +0000 (-0700) Subject: mm: hwpoison: remove the unnecessary THP check X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c7cb42e94473aafe553c0f2a3d8ca904599399ed;p=linux.git mm: hwpoison: remove the unnecessary THP check When handling THP hwpoison checked if the THP is in allocation or free stage since hwpoison may mistreat it as hugetlb page. After commit 415c64c1453a ("mm/memory-failure: split thp earlier in memory error handling") the problem has been fixed, so this check is no longer needed. Remove it. The side effect of the removal is hwpoison may report unsplit THP instead of unknown error for shmem THP. It seems not like a big deal. The following patch "mm: filemap: check if THP has hwpoisoned subpage for PMD page fault" depends on this, which fixes shmem THP with hwpoisoned subpage(s) are mapped PMD wrongly. So this patch needs to be backported to -stable as well. Link: https://lkml.kernel.org/r/20211020210755.23964-2-shy828301@gmail.com Signed-off-by: Yang Shi Suggested-by: Naoya Horiguchi Acked-by: Naoya Horiguchi Cc: Hugh Dickins Cc: Kirill A. Shutemov Cc: Matthew Wilcox Cc: Oscar Salvador Cc: Peter Xu Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 3e6449f2102a7..73f68699e7ab4 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1147,20 +1147,6 @@ static int __get_hwpoison_page(struct page *page) if (!HWPoisonHandlable(head)) return -EBUSY; - if (PageTransHuge(head)) { - /* - * Non anonymous thp exists only in allocation/free time. We - * can't handle such a case correctly, so let's give it up. - * This should be better than triggering BUG_ON when kernel - * tries to touch the "partially handled" page. - */ - if (!PageAnon(head)) { - pr_err("Memory failure: %#lx: non anonymous thp\n", - page_to_pfn(page)); - return 0; - } - } - if (get_page_unless_zero(head)) { if (head == compound_head(page)) return 1;