From: Bart Van Assche <Bart.VanAssche@sandisk.com>
To: "tom.leiming@gmail.com" <tom.leiming@gmail.com>
CC: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "hch@infradead.org" <hch@infradead.org>,
        "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
        "yizhan@redhat.com" <yizhan@redhat.com>, "axboe@fb.com" <axboe@fb.com>,
        "stable@vger.kernel.org" <stable@vger.kernel.org>
Subject: Re: [PATCH 1/2] blk-mq: don't complete un-started request in
 timeout handler
Thread-Topic: [PATCH 1/2] blk-mq: don't complete un-started request in
 timeout handler
Thread-Index: AQHSnp1KEX2eoVjOJEqb7jYtuzuSHw==
Date: Thu, 16 Mar 2017 21:35:54 +0000
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On Thu, 2017-03-16 at 08:07 +0800, Ming Lei wrote:
> > * Check whether REQ_ATOM_STARTED has been set.
> > * Check whether REQ_ATOM_COMPLETE has not yet been set.
> > * If both conditions have been met, set REQ_ATOM_COMPLETE.
> > 
> > I don't think there is another solution than using a single state variable to
> > represent the REQ_ATOM_STARTED and REQ_ATOM_COMPLETE states instead of two
> > independent bits. How about the patch below?
> 
> I would review it if you can confirm me that it is a real issue, :-)

Hello Ming,

I was chasing a v4.11 regression in the SCSI stack. Since my tests of today
revealed that it's probably not a block layer issue, let's proceed with your
patch.

Bart.