The patch titled
Subject: mm: remove folio from deferred split list before uncharging it
has been added to the -mm mm-unstable branch. Its filename is
mm-remove-folio-from-deferred-split-list-before-uncharging-it.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-remove-folio-from-deferred-split-list-before-uncharging-it.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm: remove folio from deferred split list before uncharging it
Date: Sun, 10 Mar 2024 13:48:48 +0000
When freeing a large folio, we must remove it from the deferred split list
before we uncharge it as each memcg has its own deferred split list (with
associated lock) and removing a folio from the deferred split list while
holding the wrong lock will corrupt that list and cause various related
problems.
Link: https://lore.kernel.org/linux-mm/367a14f7-340e-4b29-90ae-bc3fcefdd5f4@xxxxxxx/
Link: https://lkml.kernel.org/r/20240310134850.3825782-1-willy@xxxxxxxxxxxxx
Fixes: f77171d241e3 (mm: allow non-hugetlb large folios to be batch processed)
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Debugged-by: Ryan Roberts <ryan.roberts@xxxxxxx>
Tested-by: Ryan Roberts <ryan.roberts@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/swap.c | 2 ++
1 file changed, 2 insertions(+)
--- a/mm/swap.c~mm-remove-folio-from-deferred-split-list-before-uncharging-it
+++ a/mm/swap.c
@@ -1012,6 +1012,8 @@ void folios_put_refs(struct folio_batch
free_huge_folio(folio);
continue;
}
+ if (folio_test_large(folio) && folio_test_large_rmappable(folio))
+ folio_undo_large_rmappable(folio);
__page_cache_release(folio, &lruvec, &flags);
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
mm-remove-folio-from-deferred-split-list-before-uncharging-it.patch
mm-fix-list-corruption-in-put_pages_list.patch
