Re: FAILED: patch "[PATCH] btrfs: don't double lock the subvol_sem for rename exchange" failed to apply to 4.9-stable tree

[Sasha Levin <sashal@kernel.org>]

On Mon, Dec 23, 2019 at 12:11:14PM -0500, gregkh@linuxfoundation.org wrote:
>
>The patch below does not apply to the 4.9-stable tree.
>If someone wants it applied there, or to any other stable or longterm
>tree, then please email the backport, including the original git commit
>id to <stable@vger.kernel.org>.
>
>thanks,
>
>greg k-h
>
>------------------ original commit in Linus's tree ------------------
>
>From 943eb3bf25f4a7b745dd799e031be276aa104d82 Mon Sep 17 00:00:00 2001
>From: Josef Bacik <josef@toxicpanda.com>
>Date: Tue, 19 Nov 2019 13:59:20 -0500
>Subject: [PATCH] btrfs: don't double lock the subvol_sem for rename exchange
>
>If we're rename exchanging two subvols we'll try to lock this lock
>twice, which is bad.  Just lock once if either of the ino's are subvols.
>
>Fixes: cdd1fedf8261 ("btrfs: add support for RENAME_EXCHANGE and RENAME_WHITEOUT")
>CC: stable@vger.kernel.org # 4.4+
>Signed-off-by: Josef Bacik <josef@toxicpanda.com>
>Reviewed-by: David Sterba <dsterba@suse.com>
>Signed-off-by: David Sterba <dsterba@suse.com>

I've fixed it up and queued for 4.9. I don't think it needs to go to 4.4
as cdd1fedf8261 isn't in 4.4.

-- 
Thanks,
Sasha