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Subject: Re: [PATCH v2] nvme-tcp: Check if request has started before
 processing it
To:     "Ewan D. Milne" <emilne@redhat.com>,
        Hannes Reinecke <hare@suse.de>, Keith Busch <kbusch@kernel.org>
Cc:     Daniel Wagner <dwagner@suse.de>, linux-nvme@lists.infradead.org,
        linux-kernel@vger.kernel.org, Jens Axboe <axboe@fb.com>,
        Christoph Hellwig <hch@lst.de>
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From:   Sagi Grimberg <sagi@grimberg.me>
Message-ID: <5715ef78-eaf1-dcb6-c2a2-f4725e1a01c4@grimberg.me>
Date:   Wed, 31 Mar 2021 15:24:49 -0700
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>> What we can do, though, is checking the 'state' field in the tcp
>> request, and only allow completions for commands which are in a state
>> allowing for completions.
>>
>> Let's see if I can whip up a patch.
> 
> That would be great.  BTW in the crash dump I am looking at now, it
> looks like pdu->command_id was zero in nvme_tcp_recv_data(), and
> blk_mq_tag_to_rq() returned a request struct that had not been used.
> So I think we do need to check that the tag was actually allocated.

request tag can't be zero? I forget...