ext4: don't mark mmp buffer head dirty

Marking mmp bh dirty before writing it will make writeback
pick up mmp block later and submit a write, we don't want the
duplicate write as kmmpd thread should have full control of
reading and writing the mmp block.
Another reason is we will also have random I/O error on
the writeback request when blk integrity is enabled, because
kmmpd could modify the content of the mmp block(e.g. setting
new seq and time) while the mmp block is under I/O requested
by writeback.

Signed-off-by: Li Dongyang <dongyangli@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Cc: stable@vger.kernel.org
This commit is contained in:
Li Dongyang 2018-09-15 17:11:25 -04:00 committed by Theodore Ts'o
parent 338affb548
commit fe18d64989

View File

@ -49,7 +49,6 @@ static int write_mmp_block(struct super_block *sb, struct buffer_head *bh)
*/
sb_start_write(sb);
ext4_mmp_csum_set(sb, mmp);
mark_buffer_dirty(bh);
lock_buffer(bh);
bh->b_end_io = end_buffer_write_sync;
get_bh(bh);