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| author | Usama Arif <usamaarif642@gmail.com> | 2024-12-12 18:33:51 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-27 14:02:20 +0100 |
| commit | a086c8d7f2797c23434baaa4aae0a6bae5dc3414 (patch) | |
| tree | 1ca4130da24abb1ca0db94465bfe112ad786679a /include/linux | |
| parent | a095090b70157442c1790f3052b104b909b363e2 (diff) | |
| download | linux-a086c8d7f2797c23434baaa4aae0a6bae5dc3414.tar.gz linux-a086c8d7f2797c23434baaa4aae0a6bae5dc3414.tar.bz2 linux-a086c8d7f2797c23434baaa4aae0a6bae5dc3414.zip | |
mm: convert partially_mapped set/clear operations to be atomic
commit 42b2eb69835b0fda797f70eb5b4fc213dbe3a7ea upstream.
Other page flags in the 2nd page, like PG_hwpoison and PG_anon_exclusive
can get modified concurrently. Changes to other page flags might be lost
if they are happening at the same time as non-atomic partially_mapped
operations. Hence, make partially_mapped operations atomic.
Link: https://lkml.kernel.org/r/20241212183351.1345389-1-usamaarif642@gmail.com
Fixes: 8422acdc97ed ("mm: introduce a pageflag for partially mapped folios")
Reported-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/all/e53b04ad-1827-43a2-a1ab-864c7efecf6e@redhat.com/
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Barry Song <baohua@kernel.org>
Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Nico Pache <npache@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Yu Zhao <yuzhao@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/page-flags.h | 12 |
1 files changed, 2 insertions, 10 deletions
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 74aa9fbbdae7..48c66b846682 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -860,18 +860,10 @@ static inline void ClearPageCompound(struct page *page) ClearPageHead(page); } FOLIO_FLAG(large_rmappable, FOLIO_SECOND_PAGE) -FOLIO_TEST_FLAG(partially_mapped, FOLIO_SECOND_PAGE) -/* - * PG_partially_mapped is protected by deferred_split split_queue_lock, - * so its safe to use non-atomic set/clear. - */ -__FOLIO_SET_FLAG(partially_mapped, FOLIO_SECOND_PAGE) -__FOLIO_CLEAR_FLAG(partially_mapped, FOLIO_SECOND_PAGE) +FOLIO_FLAG(partially_mapped, FOLIO_SECOND_PAGE) #else FOLIO_FLAG_FALSE(large_rmappable) -FOLIO_TEST_FLAG_FALSE(partially_mapped) -__FOLIO_SET_FLAG_NOOP(partially_mapped) -__FOLIO_CLEAR_FLAG_NOOP(partially_mapped) +FOLIO_FLAG_FALSE(partially_mapped) #endif #define PG_head_mask ((1UL << PG_head)) |