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From:   "Stephen R. van den Berg" <srb@cuci.nl>
To:     Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc:     Btrfs BTRFS <linux-btrfs@vger.kernel.org>
Subject: qgroup: Don't trigger backref walk at delayed ref insert time (Re:
 Kernel traces)
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Qu Wenruo wrote:
>It's caused by qgroup, and a dead lock on btrfs_drop_snapshot().

>This is one of the easiest way to trigger an ABBA deadlock.

>Please either disable qgroup or apply this patch to solve it:
>https://patchwork.kernel.org/patch/10725371/

Can anyone confirm that patch https://patchwork.kernel.org/patch/10725371/
(qgroup: Don't trigger backref walk at delayed ref insert time)
is present in mainline Linux kernel v5.2.2 ?

I seem to be getting a conflict on merging that patch with this kernel.
-- 
Stephen.