From mboxrd@z Thu Jan  1 00:00:00 1970
From: keith.busch@linux.intel.com (Keith Busch)
Date: Mon, 21 May 2018 08:22:19 -0600
Subject: [PATCH 3/6] nvme: Move all IO out of controller reset
In-Reply-To: <20180518230357.GC18334@ming.t460p>
References: <20180518163823.27820-1-keith.busch@intel.com>
 <20180518163823.27820-3-keith.busch@intel.com>
 <20180518230357.GC18334@ming.t460p>
Message-ID: <20180521142219.GC5528@localhost.localdomain>

On Sat, May 19, 2018@07:03:58AM +0800, Ming Lei wrote:
> On Fri, May 18, 2018@10:38:20AM -0600, Keith Busch wrote:
> > +
> > +	if (unfreeze)
> > +		nvme_wait_freeze(&dev->ctrl);
> > +
> 
> timeout may comes just before&during blk_mq_update_nr_hw_queues() or
> the above nvme_wait_freeze(), then both two may hang forever.

Why would it hang forever? The scan_work doesn't stop a timeout from
triggering a reset to reclaim requests necessary to complete a freeze.