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Date:   Tue, 21 May 2019 11:01:03 +0200
From:   David Sterba <dsterba@suse.cz>
To:     Dennis Zhou <dennis@kernel.org>
Cc:     David Sterba <dsterba@suse.com>,
        Josef Bacik <josef@toxicpanda.com>, Chris Mason <clm@fb.com>,
        linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel-team@fb.com, "Erhard F ." <erhard_f@mailbox.org>
Subject: Re: [PATCH] btrfs: correct zstd workspace manager lock to use
 spin_lock_bh()
Message-ID: <20190521090103.GH3138@twin.jikos.cz>
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References: <20190517231626.85614-1-dennis@kernel.org>
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On Fri, May 17, 2019 at 07:16:26PM -0400, Dennis Zhou wrote:
> The btrfs zstd workspace manager uses a background timer to reclaim
> not recently used workspaces. I dumbly call spin_lock() from this
> context which I should have caught with lockdep but.. This deadlock was
> reported in [1]. The fix is to switch the zstd wsm lock to use
> spin_lock_bh().
> 
> [1] https://bugzilla.kernel.org/show_bug.cgi?id=203517
> 
> Signed-off-by: Dennis Zhou <dennis@kernel.org>

Reviewed-by: David Sterba <dsterba@suse.com>

Added to 5.2-rc queue, thanks.