commit b1ee26b "radeonfb: accelerate imageblit and other improvements" freezes system on switching from X to text console

commit b1ee26b "radeonfb: accelerate imageblit and other improvements" freezes system on switching from X to text console

[Gaudenz Steinlin]

Hi Ben

The changes in the commit mentioned in the subject freeze my system when
changing from X to a text console. The system freezes with a garbled
display. Reverting this commit fixes the problem.

The freeze only happens if DRI is enabled in X. It also does not happen
if I simply switch between different text consoles. 

My system is a PowerPC PowerBook G4 15" (PowerBook5,8) with a ATI
Mobility Radeon 9600 M10 graphics card. I'm running X.org 1.5.1 with the
radeon driver version 6.9.0+git20080826.a3cc1d7a from Debian
experimental.

Sorry, I don't have the knowledge nor the time to fix this myself, but I
would be happy to test an improved patch. Please also feel free to ask
if you need more information.

Gaudenz

-- 
Ever tried. Ever failed. No matter.
Try again. Fail again. Fail better.
~ Samuel Beckett ~

Re: commit b1ee26b "radeonfb: accelerate imageblit and other improvements" freezes system on switching from X to text console

[Gaudenz Steinlin]

On Tue, Nov 25, 2008 at 08:44:57PM +0100, Gaudenz Steinlin wrote:
> Hi Ben
> 
> The changes in the commit mentioned in the subject freeze my system when
> changing from X to a text console. The system freezes with a garbled
> display. Reverting this commit fixes the problem.
> 
> The freeze only happens if DRI is enabled in X. It also does not happen
> if I simply switch between different text consoles. 
> 

OK, I searched a bit more and found
http://bugzilla.kernel.org/show_bug.cgi?id=11875 which is possibly
related. I also found the patch Ben proposed to fix this at
http://lkml.org/lkml/2008/11/10/12. Unfortunately this patch did not fix
my problem. 

Gaudenz

-- 
Ever tried. Ever failed. No matter.
Try again. Fail again. Fail better.
~ Samuel Beckett ~

Re: commit b1ee26b "radeonfb: accelerate imageblit and other improvements" freezes system on switching from X to text console

[Benjamin Herrenschmidt]

On Tue, 2008-11-25 at 20:44 +0100, Gaudenz Steinlin wrote:
> Hi Ben
> 
> The changes in the commit mentioned in the subject freeze my system when
> changing from X to a text console. The system freezes with a garbled
> display. Reverting this commit fixes the problem.
> 
> The freeze only happens if DRI is enabled in X. It also does not happen
> if I simply switch between different text consoles. 
> 
> My system is a PowerPC PowerBook G4 15" (PowerBook5,8) with a ATI
> Mobility Radeon 9600 M10 graphics card. I'm running X.org 1.5.1 with the
> radeon driver version 6.9.0+git20080826.a3cc1d7a from Debian
> experimental.
> 
> Sorry, I don't have the knowledge nor the time to fix this myself, but I
> would be happy to test an improved patch. Please also feel free to ask
> if you need more information.

It's annoying as I have approximately the same machine and couldn't
reproduce the problem lately (slightly different X version though, from
Ubuntu intrepid).

I'll give it another go.

Cheers,
Ben.

Re: commit b1ee26b "radeonfb: accelerate imageblit and other improvements" freezes system on switching from X to text console

[Benjamin Herrenschmidt]

On Wed, 2008-11-26 at 00:13 +0100, Gaudenz Steinlin wrote:
> On Tue, Nov 25, 2008 at 08:44:57PM +0100, Gaudenz Steinlin wrote:
> > Hi Ben
> > 
> > The changes in the commit mentioned in the subject freeze my system when
> > changing from X to a text console. The system freezes with a garbled
> > display. Reverting this commit fixes the problem.
> > 
> > The freeze only happens if DRI is enabled in X. It also does not happen
> > if I simply switch between different text consoles. 
> > 
> 
> OK, I searched a bit more and found
> http://bugzilla.kernel.org/show_bug.cgi?id=11875 which is possibly
> related. I also found the patch Ben proposed to fix this at
> http://lkml.org/lkml/2008/11/10/12. Unfortunately this patch did not fix
> my problem. 

The fix is for a different problem. I suspect the root cause is a bug in
X but I'm still trying to track it down.

I think I'll just do a patch that make the new acceleration conditional
on a kernel command line option for .28 final ...

Cheers,
Ben.