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Date: Fri, 30 Mar 2007 15:19:26 +0200
From: Cornelia Huck <cornelia.huck@de.ibm.com>
To: Tejun Heo <htejun@gmail.com>
Cc: gregkh@suse.de, hugh@veritas.com, dmitry.torokhov@gmail.com,
       oneukum@suse.de, maneesh@in.ibm.com, rpurdie@rpsys.net,
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       "linux-ide@vger.kernel.org" <linux-ide@vger.kernel.org>,
       SCSI Mailing List <linux-scsi@vger.kernel.org>
Subject: Re: [RFD driver-core] Lifetime problems of the current driver model
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On Fri, 30 Mar 2007 18:43:02 +0900,
Tejun Heo <htejun@gmail.com> wrote:

> One way to solve this problem is to subordinate lifetime rule #b to
> rule #c.  Each kobject points to its owning module such that grabbing
> a kobject automatically grabs the module.  The problem with this
> approach is that it requires wide update and makes kobject_get
> heavier.

Shouldn't getting/putting the module refcount be solely done in
kobject.c? Grab the module reference when the kobject is created and
release the module reference in kobject_cleanup() after the release
function has been called. This doesn't make kobject_get() heavier, and
it ensures we don't delete the module until after the last kobject it is
supposed to clean up has been released.