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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: [patch 1/2] powerpc: rmb fix
Date: Thu, 23 Aug 2007 19:49:17 +0200
To: Nick Piggin <npiggin@suse.de>
Cc: linuxppc-dev@ozlabs.org, Paul Mackerras <paulus@samba.org>
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>>> Drivers are definitely using these __raw_ accessors, and from a quick
>>> look, they do appear to be hoping that *mb() is going to order access
>>> for
>>> them.
>>
>> Which drivers?
>
> There are maybe a dozen that use the raw accessors, and use non-smp_
> memory barriers. I just looked at drivers/video/tgafb.c, which
> indeed appears to intermix them.

Hrm yeah.  It also looks like old buggy code that could use a
cleanup or two (or three or four).  I wonder if all __raw_ users
are like that?


Segher