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Subject: Re: [PATCH] nvme-tcp: Check if request has started before processing
 it
To:     Daniel Wagner <dwagner@suse.de>, linux-nvme@lists.infradead.org
Cc:     linux-kernel@vger.kernel.org, Christoph Hellwig <hch@lst.de>,
        Jens Axboe <axboe@fb.com>, Keith Busch <kbusch@kernel.org>,
        Hannes Reinecke <hare@suse.de>
References: <20210212181738.79274-1-dwagner@suse.de>
From:   Sagi Grimberg <sagi@grimberg.me>
Message-ID: <c3a682d3-58f7-f5cc-caaa-75c36ca464e2@grimberg.me>
Date:   Fri, 12 Feb 2021 12:58:27 -0800
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> blk_mq_tag_to_rq() will always return a request if the command_id is
> in the valid range. Check if the request has been started. If we
> blindly process the request we might double complete a request which
> can be fatal.

How did you get to this one? did the controller send a completion for
a completed/bogus request?