path: root/mm
diff options
authorHugh Dickins <hughd@google.com>2012-06-02 00:27:47 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-06-03 20:05:47 -0700
commit752dc185dacba1edcba425e67fc6df3c7793a5c3 (patch)
treea2e05a91cff7d1549ba5fcaa3f583339db3412f1 /mm
parentvfs: move inode stat information closer together (diff)
mm: fix warning in __set_page_dirty_nobuffers
New tmpfs use of !PageUptodate pages for fallocate() is triggering the WARNING: at mm/page-writeback.c:1990 when __set_page_dirty_nobuffers() is called from migrate_page_copy() for compaction. It is anomalous that migration should use __set_page_dirty_nobuffers() on an address_space that does not participate in dirty and writeback accounting; and this has also been observed to insert surprising dirty tags into a tmpfs radix_tree, despite tmpfs not using tags at all. We should probably give migrate_page_copy() a better way to preserve the tag and migrate accounting info, when mapping_cap_account_dirty(). But that needs some more work: so in the interim, avoid the warning by using a simple SetPageDirty on PageSwapBacked pages. Reported-and-tested-by: Dave Jones <davej@redhat.com> Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
1 files changed, 4 insertions, 1 deletions
diff --git a/mm/migrate.c b/mm/migrate.c
index ab81d482ae6f..be26d5cbe56b 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -436,7 +436,10 @@ void migrate_page_copy(struct page *newpage, struct page *page)
* is actually a signal that all of the page has become dirty.
* Whereas only part of our page may be dirty.
- __set_page_dirty_nobuffers(newpage);
+ if (PageSwapBacked(page))
+ SetPageDirty(newpage);
+ else
+ __set_page_dirty_nobuffers(newpage);
mlock_migrate_page(newpage, page);