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Date:   Tue, 20 Jun 2000 02:06:47 +1000
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From:   Andrew Morton <andrewm@uow.edu.au>
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To:     Keith Owens <kaos@ocs.com.au>
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Subject: Re: modular net drivers
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            19 Jun 2000 23:54:30 +1000." <394E2616.C25F8376@uow.edu.au> <4516.961428041@ocs3.ocs-net>
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Keith Owens wrote:
> 
> Racy.  The module referred to by dev->owner might be in the middle of
> being unloaded.  You need try_inc_mod_count() with a check on its
> result instead of __MOD_INC_USE_COUNT.

eww.  That would mean the existing code is racy.  I assumed it took care
of this elsewhere. Maybe not.  try_inc_mod_count looks good.


Petr Vandrovec wrote:
> 
> 
> You should change it to
>     if (dev->owner)
>         __MOD_INC_USE_COUNT(dev->owner);
>     if (dev->open)
>         ret = dev->open(dev);
>     if (ret != 0 && dev->owner)
>         __MOD_DEC_USE_COUNT(dev->owner);
>     ...

<slaps head>