From: Yu Kuai <yukuai3@xxxxxxxxxx> The lockdep assert is added by commit a448af25becf ("md/raid10: remove rcu protection to access rdev from conf") in print_conf(). And I didn't notice that dm-raid is calling "pers->hot_add_disk" without holding 'reconfig_mutex'. "pers->hot_add_disk" read and write many fields that is protected by 'reconfig_mutex', and raid_resume() already grab the lock in other contex. Hence fix this problem by protecting "pers->host_add_disk" with the lock. Fixes: 9092c02d9435 ("DM RAID: Add ability to restore transiently failed devices on resume") Fixes: a448af25becf ("md/raid10: remove rcu protection to access rdev from conf") Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx> --- drivers/md/dm-raid.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index 16d3348abfed..5f78cc19d6f3 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -4077,7 +4077,9 @@ static void raid_resume(struct dm_target *ti) * Take this opportunity to check whether any failed * devices are reachable again. */ + mddev_lock_nointr(mddev); attempt_restore_of_faulty_devices(rs); + mddev_unlock(mddev); } if (test_and_clear_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) { -- 2.39.2