From mboxrd@z Thu Jan  1 00:00:00 1970
From: Greg KH <gregkh@suse.de>
Subject: Re: [RFC 22/22] tcm_loop: Add multi-fabric Linux/SCSI LLD fabric
	module
Date: Sun, 5 Sep 2010 22:17:03 -0700
Message-ID: <20100906051703.GA2891@suse.de>
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To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>, linux-scsi <linux-scsi@vger.kernel.org>, linux-kernel <linux-kernel@vger.kernel.org>, FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>, Mike Christie <michaelc@cs.wisc.edu>, Christoph Hellwig <hch@lst.de>, Hannes Reinecke <hare@suse.de>, James Bottomley <James.Bottomley@suse.de>, Jens Axboe <axboe@kernel.dk>, Boaz Harrosh <bharrosh@panasas.com>

On Sun, Sep 05, 2010 at 10:08:16PM -0700, Dmitry Torokhov wrote:
> On Sun, Sep 05, 2010 at 02:51:19PM -0700, Nicholas A. Bellinger wrote:
> > On Sun, 2010-09-05 at 13:30 -0700, Dmitry Torokhov wrote:
> > > On Mon, Aug 30, 2010 at 02:23:23AM -0700, Nicholas A. Bellinger wrote:
> > > > +
> > > > +static void tcm_loop_primary_release(struct device *dev)
> > > > +{
> > > > +	return;
> > > > +}
> > > > +
> > > > +static struct device tcm_loop_primary = {
> > > > +	.init_name		= "tcm_loop_0",
> > > > +	.release		= tcm_loop_primary_release,
> > > > +};
> > > > +
> > > 
> > > No, you can not have statically allocated devices and dummy release
> > > functions.
> > > 
> > 
> > Last time I checked this is still what mainline
> > drivers/scsi/scsi_debug.c is doing for struct device pseudo_primary:
> > 
> > static void pseudo_0_release(struct device *dev)
> > {
> >         if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
> >                 printk(KERN_INFO "scsi_debug: pseudo_0_release() called\n");
> > }
> > 
> > static struct device pseudo_primary = {
> >         .init_name      = "pseudo_0",
> >         .release        = pseudo_0_release,
> > };
> > 
> > so for these type of things in TCM_Loop I tend to follow what scsi_debug does,
> >  so I don't exactly see a issue here atm.  Anybody else have comments..?
> 
> The kobject embedded in the device structure is refcounted and it's
> lifetime may be different from lifetime of your module. If somebody
> happen to hold reference to the driver while your module is being
> unloaded bad things will happen.
> 
> I am sure Greg has something on this topic ready for cut-and-paste.

Documentation/kobject.txt :)