From mboxrd@z Thu Jan  1 00:00:00 1970
From: James Bottomley <jbottomley@parallels.com>
Subject: Re: [PATCH v12 5/6] Avoid that scsi_device_set_state() triggers a
 race
Date: Mon, 1 Jul 2013 14:49:55 +0000
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References: <51CC5176.90609@acm.org> <51CC52A5.2010204@acm.org>
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To: Bart Van Assche <bvanassche@acm.org>
Cc: Mike Christie <michaelc@cs.wisc.edu>, Hannes Reinecke <hare@suse.de>, Chanho Min <chanho.min@lge.com>, Joe Lawrence <jdl1291@gmail.com>, linux-scsi <linux-scsi@vger.kernel.org>, David Milburn <dmilburn@redhat.com>, Tejun Heo <tj@kernel.org>


On Thu, 2013-06-27 at 16:56 +0200, Bart Van Assche wrote:
> Make concurrent invocations of scsi_device_set_state() safe.

Firstly, I don't understand from this where you think the races are.
Secondly, shouldn't this be the device lock? and thirdly, if we accept
that locking is required, encapsulate it in the function: Having the
callers manage locking is asking for trouble.  The latter may require a
new lock for the state to avoid entanglement.

James