Patch "md/linear: shutup lockdep warnning" has been added to the 4.9-stable tree

Patch "md/linear: shutup lockdep warnning" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    md/linear: shutup lockdep warnning

to the 4.9-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:
     md-linear-shutup-lockdep-warnning.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Oct 19 15:04:02 CEST 2017
From: Shaohua Li <shli@fb.com>
Date: Tue, 21 Feb 2017 11:57:01 -0800
Subject: md/linear: shutup lockdep warnning

From: Shaohua Li <shli@fb.com>


[ Upstream commit d939cdfde34f50b95254b375f498447c82190b3e ]

Commit 03a9e24(md linear: fix a race between linear_add() and
linear_congested()) introduces the warnning.

Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/md/linear.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/md/linear.c
+++ b/drivers/md/linear.c
@@ -223,7 +223,8 @@ static int linear_add(struct mddev *mdde
 	 * oldconf until no one uses it anymore.
 	 */
 	mddev_suspend(mddev);
-	oldconf = rcu_dereference(mddev->private);
+	oldconf = rcu_dereference_protected(mddev->private,
+			lockdep_is_held(&mddev->reconfig_mutex));
 	mddev->raid_disks++;
 	WARN_ONCE(mddev->raid_disks != newconf->raid_disks,
 		"copied raid_disks doesn't match mddev->raid_disks");


Patches currently in stable-queue which might be from shli@fb.com are

queue-4.9/md-linear-shutup-lockdep-warnning.patch