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Date: Tue, 2 Jul 2002 01:11:56 -0300
From: Werner Almesberger <wa@almesberger.net>
To: Keith Owens <kaos@ocs.com.au>
Cc: linux-kernel@vger.kernel.org
Subject: Re: RE2: [OKS] Module removal
Message-ID: <20020702011156.E2295@almesberger.net>
References: <20020702001152.D2295@almesberger.net> <31775.1025581336@kao2.melbourne.sgi.com>
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Keith Owens wrote:
> Incrementing the use count at registration time is no good, it stops
> the module being unloaded.  Operations are deregistered at rmmod time.
> Setting the use count at registration prevents rmmod from removing the
> module, so you cannot deregister the operations.  Catch 22.

But those references go through the module exit function, which
acts like an implicit reference counter. So as long as

 - module exit de-registers all of them (if it doesn't, we're
   screwed anyhow), and
 - the registry itself isn't racy (if it is, this is likely to
   surface in other circumstances too, e.g. if a driver destroys
   internal state immediately after de-registration)

they should be safe, shouldn't they ?

- Werner

P.S. mail.ocs.com.au thinks I'm a spammer :-(

-- 
  _________________________________________________________________________
 / Werner Almesberger, Buenos Aires, Argentina         wa@almesberger.net /
/_http://icapeople.epfl.ch/almesber/_____________________________________/
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