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Date:   Wed, 25 Aug 2021 16:19:27 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc:     Christoph Hellwig <hch@lst.de>, Josef Bacik <josef@toxicpanda.com>,
        Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org
Subject: Re: [PATCH] nbd: Fix races introduced by nbd_index_mutex scope
 reduction
Message-ID: <20210825141927.GA24861@lst.de>
References: <40c3ff83-3fce-5408-9579-7df5f9999450@i-love.sakura.ne.jp> <20210825131519.GA19907@lst.de> <16109a71-c366-b27e-8501-51e7fe950729@i-love.sakura.ne.jp> <20210825141847.GA24740@lst.de>
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On Wed, Aug 25, 2021 at 04:18:47PM +0200, Christoph Hellwig wrote:
> On Wed, Aug 25, 2021 at 10:38:00PM +0900, Tetsuo Handa wrote:
> > I guess you might want below diff, for reinit_completion() immediately after
> > complete_all() likely resets completion count before all threads sleeping at
> > wait_for_completion_timeout() check the completion count.
> > Use of simple sequence count will be robuster.
> 
> Yes, this is very simple to what I have locally.

s/simple/similar/