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Date:   Thu, 22 Sep 2022 10:13:25 +0800
From:   Ming Lei <ming.lei@redhat.com>
To:     ZiyangZhang <ZiyangZhang@linux.alibaba.com>
Cc:     axboe@kernel.dk, xiaoguang.wang@linux.alibaba.com,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        joseph.qi@linux.alibaba.com
Subject: Re: [PATCH V4 6/8] ublk_drv: support UBLK_F_USER_RECOVERY_REISSUE
Message-ID: <YyvExQcnSFAqQHMY@T590>
References: <20220921095849.84988-1-ZiyangZhang@linux.alibaba.com>
 <20220921095849.84988-7-ZiyangZhang@linux.alibaba.com>
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In-Reply-To: <20220921095849.84988-7-ZiyangZhang@linux.alibaba.com>
Precedence: bulk

On Wed, Sep 21, 2022 at 05:58:47PM +0800, ZiyangZhang wrote:
> UBLK_F_USER_RECOVERY_REISSUE implies that:
> With a dying ubq_daemon, ublk_drv let monitor_work requeues rq issued to
> userspace(ublksrv) before the ubq_daemon is dying.
> 
> UBLK_F_USER_RECOVERY_REISSUE is designed for backends which:
> (1) tolerate double-write since ublk_drv may issue the same rq
>     twice.
> (2) does not let frontend users get I/O error, such as read-only FS
>     and VM backend.
> 
> Signed-off-by: ZiyangZhang <ZiyangZhang@linux.alibaba.com>
> ---

Reviewed-by: Ming Lei <ming.lei@redhat.com>

Thanks,
Ming