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Date: Tue, 2 Jul 2002 00:11:52 -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: <20020702001152.D2295@almesberger.net>
References: <20020701224034.C2295@almesberger.net> <31042.1025576745@kao2.melbourne.sgi.com>
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Keith Owens wrote:
> This is just one symptom of the overall problem, which is module code
> that adjusts its use count by executing code that belongs to the
> module.  The same problem exists on entry to a module function, the
> module can be removed before MOD_INC_USE_COUNT is reached.

Ah yes, now I remember, thanks. I filed that under "improper reference
tracking". After all, why would anybody hold an uncounted reference in
the first place ?

I can understand that the exact number of references may be unknown,
e.g. if I pass a reference to some registration function, which may in
turn hand it to third parties, but why wouldn't I know that there is
at least one reference ?

If some other module B hands out uncounted references on behalf of
some module A, it would seem natural for B to make sure that it
collects them before getting unloaded (and thereby releasing A).

> 1) Do the reference counting outside the module, before it is entered.

Evil, agreed ;-)

- Werner

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