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Subject: Re: Regression: radeonfb: No synchronisation on CRT with
	linux-2.6.13-rc5
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Bodo Eggert <7eggert@gmx.de>
Cc: Kyle Moffett <mrmacman_g4@mac.com>, LKML <linux-kernel@vger.kernel.org>,
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Date: Sun, 07 Aug 2005 23:48:08 +0200
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On Sun, 2005-08-07 at 19:25 +0200, Bodo Eggert wrote:
> On Sun, 7 Aug 2005, Kyle Moffett wrote:
> > On Aug 7, 2005, at 03:51:07, Benjamin Herrenschmidt wrote:
> 
> > > Ah ! Interesting... I don't see why PREEMPT would affect radeonfb
> > > though ... Can you try something like wrapper radeon_write_mode() with
> > > preempt_disable()/preempt_enable() and tell me if it makes a
> > > difference ?
> 
> Did not help. The values used to initialize the mode seem to be wrong.
> Copying the aty directory from 2.6.12 did not help, too.

I don't see how PREEMPT could have any impact there unless you are
experiencing memory corruption... or one of those panels that have so
subtle timing issues that they sometimes don't sync depending on how
many flies you have in your room....

Ben.