This is a note to let you know that I've just added the patch titled
dm-raid: fix lockdep waring in "pers->hot_add_disk"
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
dm-raid-fix-lockdep-waring-in-pers-hot_add_disk.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1b3818962a987bdc835b4603c3028f209b754aa5
Author: Yu Kuai <yukuai3@xxxxxxxxxx>
Date: Tue Mar 5 15:23:06 2024 +0800
dm-raid: fix lockdep waring in "pers->hot_add_disk"
[ 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@xxxxxxxxxxxxxxx # v6.7+
Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
Signed-off-by: Xiao Ni <xni@xxxxxxxxxx>
Acked-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Song Liu <song@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240305072306.2562024-10-yukuai1@xxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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)) {
