4.19-stable review patch. If anyone has any objections, please let me know.
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From: Yu Kuai yukuai3@huawei.com
[ Upstream commit 95009ae904b1e9dca8db6f649f2d7c18a6e42c75 ]
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") Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai yukuai3@huawei.com Signed-off-by: Xiao Ni xni@redhat.com Acked-by: Mike Snitzer snitzer@kernel.org Signed-off-by: Song Liu song@kernel.org Link: https://lore.kernel.org/r/20240305072306.2562024-10-yukuai1@huaweicloud.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 1759134fce824..2a8746f9c6d87 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -4023,7 +4023,9 @@ 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)) {