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Date:   Tue, 26 Mar 2019 20:33:54 -0600
From:   Keith Busch <kbusch@kernel.org>
To:     "jianchao.wang" <jianchao.w.wang@oracle.com>
Cc:     Jens Axboe <axboe@kernel.dk>,
        "Busch, Keith" <keith.busch@intel.com>,
        James Smart <jsmart2021@gmail.com>,
        Bart Van Assche <bvanassche@acm.org>,
        Ming Lei <tom.leiming@gmail.com>,
        Josef Bacik <josef@toxicpanda.com>,
        linux-nvme <linux-nvme@lists.infradead.org>,
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        linux-block <linux-block@vger.kernel.org>,
        Hannes Reinecke <hare@suse.de>,
        Johannes Thumshirn <jthumshirn@suse.de>,
        Christoph Hellwig <hch@lst.de>,
        Sagi Grimberg <sagi@grimberg.me>
Subject: Re: [PATCH V2 7/8] nvme: use blk_mq_queue_tag_inflight_iter
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On Wed, Mar 27, 2019 at 10:27:57AM +0800, jianchao.wang wrote:
> As the comment above, the stable request maybe something that has been freed due to following case,
> 1. a hctx->fq.flush_rq of dead request_queue that shares the same tagset
> 2. a removed io scheduler's sched request
> and this freed request could be allocated by others which may change the field of request->state.

You're not explaing how that request->state is changed. I understand the
request can be reallocated, but what is changing its state?