[PATCH 4.18 188/350] Revert "f2fs: fix to clear PG_checked flag in set_page_dirty()"

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>

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@xxxxxxxxxxxxxxx>
Reported-and-Tested-by: Park Ju Hyung <qkrwngud825@xxxxxxxxx>
Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

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

--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2501,10 +2501,6 @@ 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)) {
 			f2fs_register_inmem_page(inode, page);