From mboxrd@z Thu Jan  1 00:00:00 1970
From: James Bottomley <James.Bottomley@HansenPartnership.com>
Subject: Re: [PATCH 6/9] scsi_dh: add generic SPC-3 alua handler
Date: Fri, 27 Jun 2008 09:38:16 -0500
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To: Hannes Reinecke <hare@suse.de>
Cc: Mike Christie <michaelc@cs.wisc.edu>, linux-scsi@vger.kernel.org

On Fri, 2008-06-27 at 16:33 +0200, Hannes Reinecke wrote:
> I cannot see how this _could_ fail, as this function is provided by
> the module, so the very existence of the function depends on the
> module. But maybe it's better to check, even so.
> 
> I'll send an updated patch.

Just because you're in the actual module it's not safe to assume
try_module_get() will succeed.  The modules have a state variable
(->state) if the user tries to remove the module, this state check will
fail in try_module_get() and it will actually return a failure.

James