dm raid: fix deadlock caused by premature md_stop_writes()
md_stop_writes() is called in raid_presuspend() causing deadlocks on
bios submitted afterwards -- which happens on loaded raid sets with
conversion requests.
Fix by moving md_stop_writes() to raid_postsuspend(). NOTE: when the
recovery's frozen (MD_RECOVERY_FROZEN), writes haven't been started (or
are already stopped) so don't stop them again.
Also remove superfluous readonly setting.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 6319d84..398314b 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -3613,24 +3613,19 @@ static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
blk_limits_io_opt(limits, chunk_size * mddev_data_stripes(rs));
}
-static void raid_presuspend(struct dm_target *ti)
-{
- struct raid_set *rs = ti->private;
-
- md_stop_writes(&rs->md);
-}
-
static void raid_postsuspend(struct dm_target *ti)
{
struct raid_set *rs = ti->private;
if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
+ /* Writes have to be stopped before suspending to avoid deadlocks. */
+ if (!test_bit(MD_RECOVERY_FROZEN, &rs->md.recovery))
+ md_stop_writes(&rs->md);
+
mddev_lock_nointr(&rs->md);
mddev_suspend(&rs->md);
mddev_unlock(&rs->md);
}
-
- rs->md.ro = 1;
}
static void attempt_restore_of_faulty_devices(struct raid_set *rs)
@@ -3903,7 +3898,6 @@ static struct target_type raid_target = {
.message = raid_message,
.iterate_devices = raid_iterate_devices,
.io_hints = raid_io_hints,
- .presuspend = raid_presuspend,
.postsuspend = raid_postsuspend,
.preresume = raid_preresume,
.resume = raid_resume,