From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH] scsi: sd_zbc: Disable zoned block devices with scsi-mq
Date: Thu, 17 Aug 2017 00:59:16 -0700
Message-ID: <20170817075916.GA28379@infradead.org>
References: <20170817024550.9845-1-damien.lemoal@wdc.com>
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To: Damien Le Moal <damien.lemoal@wdc.com>
Cc: linux-scsi@vger.kernel.org, "Martin K . Petersen" <martin.petersen@oracle.com>, Hannes Reinecke <hare@suse.de>, Christoph Hellwig <hch@lst.de>, Bart Van Assche <Bart.VanAssche@sandisk.com>

On Thu, Aug 17, 2017 at 11:45:50AM +0900, Damien Le Moal wrote:
> blk-mq may not maintain write requests order at dispatch time. So host
> managed drives will not reliably work. Worse, potential reordering of
> write requests on requeue may cause the zone write locking code to
> deadlock command dispatch to the disk. So for now, until the write
> ordering issue is fixed, do not support zoned block devices with
> scsi-mq by showing a 0 LBA capacity disk.

NAK.  Please fix the issue instead of this.