4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Theodore Ts'o <tytso@xxxxxxx>
[ Upstream commit 2dca60d98e241bea686004168f85208f215fc697 ]
Previously, when an MMP-protected file system is remounted read-only,
the kmmpd thread would exit the next time it woke up (a few seconds
later), without resetting the MMP sequence number back to
EXT4_MMP_SEQ_CLEAN.
Fix this by explicitly killing the MMP thread when the file system is
remounted read-only.
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Cc: Andreas Dilger <adilger@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ext4/mmp.c | 7 ++-----
fs/ext4/super.c | 2 ++
2 files changed, 4 insertions(+), 5 deletions(-)
--- a/fs/ext4/mmp.c
+++ b/fs/ext4/mmp.c
@@ -186,11 +186,8 @@ static int kmmpd(void *data)
goto exit_thread;
}
- if (sb_rdonly(sb)) {
- ext4_warning(sb, "kmmpd being stopped since filesystem "
- "has been remounted as readonly.");
- goto exit_thread;
- }
+ if (sb_rdonly(sb))
+ break;
diff = jiffies - last_update_time;
if (diff < mmp_update_interval * HZ)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -5163,6 +5163,8 @@ static int ext4_remount(struct super_blo
if (sbi->s_journal)
ext4_mark_recovery_complete(sb, es);
+ if (sbi->s_mmp_tsk)
+ kthread_stop(sbi->s_mmp_tsk);
} else {
/* Make sure we can mount this feature set readwrite */
if (ext4_has_feature_readonly(sb) ||
