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Date:   Tue, 29 Mar 2022 15:14:27 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Jan Kara <jack@suse.cz>
Cc:     Christoph Hellwig <hch@lst.de>,
        Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>,
        Dave Chinner <david@fromorbit.com>,
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        "Darrick J . Wong" <djwong@kernel.org>,
        Ming Lei <ming.lei@redhat.com>, linux-block@vger.kernel.org,
        nbd@other.debian.org
Subject: Re: [PATCH 12/13] loop: remove lo_refcount and avoid lo_mutex in
 ->open / ->release
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On Tue, Mar 29, 2022 at 11:42:03AM +0200, Jan Kara wrote:
> > entirely, as loop_clr_fd now is safe against concurrent users - it
> > has to anyway as there can be other users even without an open.
> 
> Ah, OK, so you'd always set LO_AUTOCLEAR and leave cleanup to happen
> from lo_release()? That makes sense to me.

No, my idea was to never set LO_AUTOCLEAR.  We have a frozen queue and
all protections in place to make clearing the file perfectly safe.
In fact the change_fd case also allows this.