提交 752dc185 编写于 作者: H Hugh Dickins 提交者: Linus Torvalds

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: NDave Jones <davej@redhat.com>
Signed-off-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
上级 2f9d3df8
......@@ -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);
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册