releases/4.19.312/dm-raid-fix-lockdep-waring-in-pers-hot_add_disk.patch

   1 From 1b3818962a987bdc835b4603c3028f209b754aa5 Mon Sep 17 00:00:00 2001
   2 From: Sasha Levin <sashal@kernel.org>
   3 Date: Tue, 5 Mar 2024 15:23:06 +0800
   4 Subject: dm-raid: fix lockdep waring in "pers->hot_add_disk"
   5
   6 From: Yu Kuai <yukuai3@huawei.com>
   7
   8 [ Upstream commit 95009ae904b1e9dca8db6f649f2d7c18a6e42c75 ]
   9
  10 The lockdep assert is added by commit a448af25becf ("md/raid10: remove
  11 rcu protection to access rdev from conf") in print_conf(). And I didn't
  12 notice that dm-raid is calling "pers->hot_add_disk" without holding
  13 'reconfig_mutex'.
  14
  15 "pers->hot_add_disk" read and write many fields that is protected by
  16 'reconfig_mutex', and raid_resume() already grab the lock in other
  17 contex. Hence fix this problem by protecting "pers->host_add_disk"
  18 with the lock.
  19
  20 Fixes: 9092c02d9435 ("DM RAID: Add ability to restore transiently failed devices on resume")
  21 Fixes: a448af25becf ("md/raid10: remove rcu protection to access rdev from conf")
  22 Cc: stable@vger.kernel.org # v6.7+
  23 Signed-off-by: Yu Kuai <yukuai3@huawei.com>
  24 Signed-off-by: Xiao Ni <xni@redhat.com>
  25 Acked-by: Mike Snitzer <snitzer@kernel.org>
  26 Signed-off-by: Song Liu <song@kernel.org>
  27 Link: https://lore.kernel.org/r/20240305072306.2562024-10-yukuai1@huaweicloud.com
  28 Signed-off-by: Sasha Levin <sashal@kernel.org>
  29 ---
  30  drivers/md/dm-raid.c | 2 ++
  31  1 file changed, 2 insertions(+)
  32
  33 diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
  34 index 1759134fce824..2a8746f9c6d87 100644
  35 --- a/drivers/md/dm-raid.c
  36 +++ b/drivers/md/dm-raid.c
  37 @@ -4023,7 +4023,9 @@ static void raid_resume(struct dm_target *ti)
  38                  * Take this opportunity to check whether any failed
  39                  * devices are reachable again.
  40                  */
  41 +               mddev_lock_nointr(mddev);
  42                 attempt_restore_of_faulty_devices(rs);
  43 +               mddev_unlock(mddev);
  44         }
  45
  46         if (test_and_clear_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
  47 --
  48 2.43.0
  49