[PATCH 4.14 110/222] Revert "f2fs: fix to clear PG_checked flag in set_page_dirty()"

Greg Kroah-Hartman
2018-11-11T22:32:40Z

From: Jaegeuk Kim <jaegeuk@kernel.org>

commit 164a63fa6b384e30ceb96ed80bc7dc3379bc0960 upstream.

This reverts commit 66110abc4c931f879d70e83e1281f891699364bf.

If we clear the cold data flag out of the writeback flow, we can miscount
-1 by end_io, which incurs a deadlock caused by all I/Os being blocked during
heavy GC.

Balancing F2FS Async:
- IO (CP: 1, Data: -1, Flush: ( 0 0 1), Discard: ( ...

GC thread: IRQ
- move_data_page()
- set_page_dirty()
- clear_cold_data()
- f2fs_write_end_io()
- type = WB_DATA_TYPE(page);
here, we get wrong type
- dec_page_count(sbi, type);
- f2fs_wait_on_page_writeback()

Cc: <stable@vger.kernel.org>
Reported-and-Tested-by: Park Ju Hyung <qkrwngud825@gmail.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/f2fs/data.c | 4 ----
1 file changed, 4 deletions(-)

--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2190,10 +2190,6 @@ static int f2fs_set_data_page_dirty(stru
if (!PageUptodate(page))
SetPageUptodate(page);

- /* don't remain PG_checked flag which was set during GC */
- if (is_cold_data(page))
- clear_cold_data(page);
-
if (f2fs_is_atomic_file(inode) && !f2fs_is_commit_atomic_write(inode)) {
if (!IS_ATOMIC_WRITTEN_PAGE(page)) {
register_inmem_page(inode, page);