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Date: Tue, 24 Apr 2007 09:46:48 +0200
From: Cornelia Huck <cornelia.huck@de.ibm.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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       linux-kernel@vger.kernel.org, Paul Mackerras <paulus@samba.org>,
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Subject: Re: [PATCH] powerpc pseries eeh: Convert to kthread API
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On Tue, 24 Apr 2007 15:00:42 +1000,
Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:

> Like anything else, modules should have separated the entrypoints for
> 
>  - Initiating a removal request
>  - Releasing the module
> 
> The former is use did "rmmod", can unregister things from subsystems,
> etc... (and can file if the driver decides to refuse removal requests
> when it's busy doing things or whatever policy that module wants to
> implement).
> 
> The later is called when all references to the modules have been
> dropped, it's a bit like the kref "release" (and could be implemented as
> one).

That sounds quite similar to the problems we have with kobject
refcounting vs. module unloading. The patchset I posted at
http://marc.info/?l=linux-kernel&m=117679014404994&w=2 exposes the
refcount of the kobject embedded in the module. Maybe the kthread code
could use that reference as well?