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Date: Wed, 11 Apr 2018 10:11:05 +0800
From: Ming Lei <ming.lei@redhat.com>
To: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        Christoph Hellwig <hch@lst.de>, Tejun Heo <tj@kernel.org>,
        Sagi Grimberg <sagi@grimberg.me>,
        Israel Rukshin <israelr@mellanox.com>,
        Max Gurtovoy <maxg@mellanox.com>, stable@vger.kernel.org
Subject: Re: [PATCH v5] blk-mq: Avoid that a completion can be ignored for
 BLK_EH_RESET_TIMER
Message-ID: <20180411021104.GC4494@ming.t460p>
References: <20180410210157.30477-1-bart.vanassche@wdc.com>
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On Tue, Apr 10, 2018 at 03:01:57PM -0600, Bart Van Assche wrote:
> The blk-mq timeout handling code ignores completions that occur after
> blk_mq_check_expired() has been called and before blk_mq_rq_timed_out()
> has reset rq->aborted_gstate. If a block driver timeout handler always
> returns BLK_EH_RESET_TIMER then the result will be that the request
> never terminates.

Under this situation:

IMO, if this request has been handled by driver's irq handler, and if
driver's .timeout still returns BLK_EH_RESET_TIMER, it is driver's bug,
and the correct return value should be BLK_EH_HANDLED.

-- 
Ming