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Date:   Fri, 8 Apr 2022 20:44:49 +0200
From:   David Sterba <dsterba@suse.cz>
To:     Schspa Shi <schspa@gmail.com>
Cc:     clm@fb.com, josef@toxicpanda.com, dsterba@suse.com,
        terrelln@fb.com, linux-btrfs@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] btrfs: zstd: use spin_lock in timer function
Message-ID: <20220408184449.GB15609@twin.jikos.cz>
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On Sat, Apr 09, 2022 at 02:15:23AM +0800, Schspa Shi wrote:
> timer callback was running on bh, and there is no need to disable bh again.

Why do you think so? There was a specific fix fee13fe96529 ("btrfs:
correct zstd workspace manager lock to use spin_lock_bh()") that
actually added the _bh, so either you need to explain why exactly it's
not needed anymore and verify that the reported lockdep warning from the
fix does not happen.