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Date:   Mon, 13 Sep 2021 17:25:58 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Hou Tao <houtao1@huawei.com>
Cc:     Christoph Hellwig <hch@lst.de>, Josef Bacik <josef@toxicpanda.com>,
        Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        nbd@other.debian.org
Subject: Re: [PATCH v2 3/3] nbd: fix race between nbd_alloc_config() and
 module removal
Message-ID: <20210913152558.GA3998@lst.de>
References: <20210904122519.1963983-1-houtao1@huawei.com> <20210904122519.1963983-4-houtao1@huawei.com> <20210906093051.GC30790@lst.de> <ce3e1ea8-ebda-4372-42ce-e8a4b2d12514@huawei.com> <20210906102521.GA3082@lst.de> <730dae5e-5af8-3554-18bf-e22ff576e2b1@huawei.com> <20210909064035.GA26290@lst.de> <6434d4e8-984d-97df-34e5-b86a0e69cf58@huawei.com>
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On Mon, Sep 13, 2021 at 12:32:37PM +0800, Hou Tao wrote:
> > Did you try just removing the extra module refcounting?
> Yes, removing the module refcounting in nbd_alloc_config() and cleaning
> the nbd_config in nbd_cleanup() also work, but not sure whether or not
> it will break some nbd user-case which depends on the extra module
> reference count. I prefer to keep the extra module refcounting considering
> that loop driver does it as well, so what is your suggestion ?

Can you respin the patch with a comment explaining this in detail
so that the next person tripping over it doesn't have to do the research
again?