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Date:   Wed, 21 Oct 2020 17:19:21 +0200
From:   David Sterba <dsterba@suse.cz>
To:     Josef Bacik <josef@toxicpanda.com>
Cc:     linux-btrfs@vger.kernel.org, kernel-team@fb.com
Subject: Re: [PATCH 1/3] btrfs: drop the path before adding qgroup items when
 enabling qgroups
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On Mon, Oct 19, 2020 at 04:02:29PM -0400, Josef Bacik wrote:
> When enabling qgroups we walk the tree_root and then add a qgroup item
> for every root that we have.  This creates a lock dependency on the
> tree_root and qgroup_root, which results in the following lockdep splat

This should mention that it's with the rwsem and that we've seen it on
btrfs/022 and btrfs/017.

That it's with rwsem is in the cover letter but we need it in the
patches too.