tree d302594fa740fcb1fd005bc29bda1a66772bf150
parent 4ba9e687ed89fd2a3fe6a3d7e95daea8669edb94
author Li Dongyang <dongyangli@ddn.com> 1537045885 -0400
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1538215654 -0700

ext4: don't mark mmp buffer head dirty

commit fe18d649891d813964d3aaeebad873f281627fbc upstream.

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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>