| From: "Matthew Wilcox (Oracle)" <willy@infradead.org> |
| Subject: mm/memory-failure: check the mapcount of the precise page |
| Date: Mon, 18 Dec 2023 13:58:36 +0000 |
| |
| A process may map only some of the pages in a folio, and might be missed |
| if it maps the poisoned page but not the head page. Or it might be |
| unnecessarily hit if it maps the head page, but not the poisoned page. |
| |
| Link: https://lkml.kernel.org/r/20231218135837.3310403-3-willy@infradead.org |
| Fixes: 7af446a841a2 ("HWPOISON, hugetlb: enable error handling path for hugepage") |
| Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> |
| Cc: Dan Williams <dan.j.williams@intel.com> |
| Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> |
| Cc: <stable@vger.kernel.org> |
| Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
| --- |
| |
| mm/memory-failure.c | 6 +++--- |
| 1 file changed, 3 insertions(+), 3 deletions(-) |
| |
| --- a/mm/memory-failure.c~mm-memory-failure-check-the-mapcount-of-the-precise-page |
| +++ a/mm/memory-failure.c |
| @@ -1570,7 +1570,7 @@ static bool hwpoison_user_mappings(struc |
| * This check implies we don't kill processes if their pages |
| * are in the swap cache early. Those are always late kills. |
| */ |
| - if (!page_mapped(hpage)) |
| + if (!page_mapped(p)) |
| return true; |
| |
| if (PageSwapCache(p)) { |
| @@ -1621,10 +1621,10 @@ static bool hwpoison_user_mappings(struc |
| try_to_unmap(folio, ttu); |
| } |
| |
| - unmap_success = !page_mapped(hpage); |
| + unmap_success = !page_mapped(p); |
| if (!unmap_success) |
| pr_err("%#lx: failed to unmap page (mapcount=%d)\n", |
| - pfn, page_mapcount(hpage)); |
| + pfn, page_mapcount(p)); |
| |
| /* |
| * try_to_unmap() might put mlocked page in lru cache, so call |
| _ |
