diff options
| author | Song Liu <songliubraving@fb.com> | 2019-09-23 15:37:47 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-09-24 15:54:11 -0700 |
| commit | 31895438e702f48e25b7aa6d88f9c97c795c79c7 (patch) | |
| tree | 6d3bf756856dcab897ef9f8cf6d284079711435a /mm/filemap.c | |
| parent | 585e5a7babd91fd85a5cc97b7324c6c2fc29e1ec (diff) | |
filemap: check compound_head(page)->mapping in pagecache_get_page()
Similar to previous patch, pagecache_get_page() avoids race condition with
truncate by checking page->mapping == mapping. This does not work for
compound pages. This patch let it check compound_head(page)->mapping
instead.
Link: http://lkml.kernel.org/r/20190801184244.3169074-3-songliubraving@fb.com
Signed-off-by: Song Liu <songliubraving@fb.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/filemap.c')
| -rw-r--r-- | mm/filemap.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index fc7818b4537e..0b301103ea80 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1647,7 +1647,7 @@ repeat: } /* Has the page been truncated? */ - if (unlikely(page->mapping != mapping)) { + if (unlikely(compound_head(page)->mapping != mapping)) { unlock_page(page); put_page(page); goto repeat; |