The patch titled
Subject: filemap: check compound_head(page)->mapping in pagecache_get_page()
has been added to the -mm tree. Its filename is
filemap-check-compound_headpage-mapping-in-pagecache_get_page.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/filemap-check-compound_headpage-mapping-in-pagecache_get_page.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/filemap-check-compound_headpage-mapping-in-pagecache_get_page.patch
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------------------------------------------------------
From: Song Liu <songliubraving@xxxxxx>
Subject: 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@xxxxxx
Signed-off-by: Song Liu <songliubraving@xxxxxx>
Suggested-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Hillf Danton <hdanton@xxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxxx>
Cc: William Kucharski <william.kucharski@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/filemap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/filemap.c~filemap-check-compound_headpage-mapping-in-pagecache_get_page
+++ a/mm/filemap.c
@@ -1648,7 +1648,7 @@ 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;
_
Patches currently in -mm which might be from songliubraving@xxxxxx are
mm-move-memcmp_pages-and-pages_identical.patch
uprobe-use-original-page-when-all-uprobes-are-removed.patch
uprobe-use-original-page-when-all-uprobes-are-removed-v2.patch
mm-thp-introduce-foll_split_pmd.patch
mm-thp-introduce-foll_split_pmd-v11.patch
uprobe-use-foll_split_pmd-instead-of-foll_split.patch
khugepaged-enable-collapse-pmd-for-pte-mapped-thp.patch
uprobe-collapse-thp-pmd-after-removing-all-uprobes.patch
filemap-check-compound_headpage-mapping-in-filemap_fault.patch
filemap-check-compound_headpage-mapping-in-pagecache_get_page.patch
filemap-update-offset-check-in-filemap_fault.patch
mmthp-stats-for-file-backed-thp.patch
khugepaged-rename-collapse_shmem-and-khugepaged_scan_shmem.patch
mmthp-add-read-only-thp-support-for-non-shmem-fs.patch
mmthp-avoid-writes-to-file-with-thp-in-pagecache.patch
