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Date:   Fri, 5 Apr 2019 05:43:45 +0800
From:   Ming Lei <ming.lei@redhat.com>
To:     Bart Van Assche <bvanassche@acm.org>
Cc:     Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        Christoph Hellwig <hch@lst.de>,
        Christoph Hellwig <hch@infradead.org>,
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        Hannes Reinecke <hare@suse.com>,
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        James Smart <james.smart@broadcom.com>,
        Dongli Zhang <dongli.zhang@oracle.com>,
        Laurence Oberman <loberman@redhat.com>, stable@vger.kernel.org
Subject: Re: [PATCH] block: Revert v5.0 blk_mq_request_issue_directly()
 changes
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On Thu, Apr 04, 2019 at 10:08:43AM -0700, Bart Van Assche wrote:
> blk_mq_try_issue_directly() can return BLK_STS*_RESOURCE for requests that
> have been queued. If that happens when blk_mq_try_issue_directly() is called
> by the dm-mpath driver then dm-mpath will try to resubmit a request that is
> already queued and a kernel crash follows. Since it is nontrivial to fix
> blk_mq_request_issue_directly(), revert the blk_mq_request_issue_directly()
> changes that went into kernel v5.0.
> 
> This patch reverts the following commits:
> * d6a51a97c0b2 ("blk-mq: replace and kill blk_mq_request_issue_directly") # v5.0.
> * 5b7a6f128aad ("blk-mq: issue directly with bypass 'false' in blk_mq_sched_insert_requests") # v5.0.
> * 7f556a44e61d ("blk-mq: refactor the code of issue request directly") # v5.0.

I am fine to revert them now.

However, could you revert them one by one so that they can be reviewed
easily?

Thanks,
Ming