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Date: Tue, 22 May 2018 14:26:58 -0600
From: Keith Busch <keith.busch@intel.com>
To: Jens Axboe <axboe@kernel.dk>
Cc: Bart Van Assche <bart.vanassche@wdc.com>, linux-block@vger.kernel.org,
	Christoph Hellwig <hch@lst.de>, Tejun Heo <tj@kernel.org>,
	Jianchao Wang <jianchao.w.wang@oracle.com>,
	Ming Lei <ming.lei@redhat.com>,
	Sebastian Ott <sebott@linux.ibm.com>,
	Sagi Grimberg <sagi@grimberg.me>,
	Israel Rukshin <israelr@mellanox.com>,
	Max Gurtovoy <maxg@mellanox.com>
Subject: Re: [PATCH v13] blk-mq: Rework blk-mq timeout handling again
Message-ID: <20180522202657.GA8961@localhost.localdomain>
References: <20180522162515.20650-1-bart.vanassche@wdc.com>
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On Tue, May 22, 2018 at 01:38:06PM -0600, Jens Axboe wrote:
> I guess it would be cleaner to actually do the transition, in
> blk_mq_rq_timed_out():
> 
>         case BLK_EH_HANDLED:                                                    
>                 if (blk_mq_change_rq_state(req, MQ_RQ_TIMED_OUT,                
>                                                 MQ_RQ_COMPLETE))                
>                         __blk_mq_complete_request(req);                         
>                 break;        
> 
> This works for me.

Works for me as well on manual fault injection tests.

I think this change above goes back to Christoph's point earlier on usage
of BLK_EH_HANDLED. Is the driver supposed to return BLK_EH_NOT_HANDLED
when the driver actually knows the request has been completed before
returning the status?