This is a note to let you know that I've just added the patch titled
mm/memory-failure: check the mapcount of the precise page
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-memory-failure-check-the-mapcount-of-the-precise-.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b6a4cc0b689cdaefddaea0c85e1600c9e6dbbe07
Author: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Date: Mon Dec 18 13:58:36 2023 +0000
mm/memory-failure: check the mapcount of the precise page
[ Upstream commit c79c5a0a00a9457718056b588f312baadf44e471 ]
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@xxxxxxxxxxxxx
Fixes: 7af446a841a2 ("HWPOISON, hugetlb: enable error handling path for hugepage")
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 3da3c63dccd1a..c971d5e11f932 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -989,7 +989,7 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn,
* 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 (PageKsm(p)) {
@@ -1033,10 +1033,10 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn,
if (kill)
collect_procs(hpage, &tokill, flags & MF_ACTION_REQUIRED);
- unmap_success = try_to_unmap(hpage, ttu);
+ unmap_success = try_to_unmap(p, ttu);
if (!unmap_success)
pr_err("Memory failure: %#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
