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From:   Keith Owens <kaos@ocs.com.au>
To:     "netdev@oss.sgi.com" <netdev@oss.sgi.com>
Subject: Re: modular net drivers, take 2 
In-reply-to: Your message of "Tue, 20 Jun 2000 17:38:57 +0200."
             <20000620173857.A4089@fred.muc.de> 
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On Tue, 20 Jun 2000 17:38:57 +0200, 
Andi Kleen <ak@muc.de> wrote:
>On Tue, Jun 20, 2000 at 02:04:35PM +0200, Andrew Morton wrote:
>> - sys_ioctl() and sys_delete_module() both already claim
>>   the big lock, so where's the race anyway?  I feel I'm missing
>>   something..
>I guess there are some time critical ioctls that should be run outside
>kernel lock though. It is far too late to audit them all though.

ioctls are not a problem, as long as they use a file descriptor, i.e.
no global ioctls.  Getting a file descriptor requires open() or its
equivalent which set the module use_count.  The race is in open, I
don't know of any races after use_count is set and open() has complete
and left the module.