Revert 737a3bb9416ce2a7c7a4170852473a4fcc9c67e8 ?

[Andy Furniss]

Michel Dänzer wrote:

>>> That does sound like the GPU locks up. Do you get any messages in dmesg
>>> about lockups and attempts to reset the GPU at any time?
>>
>> No.
>
> Hmm, I guess the constant SIGALRMs might prevent the lockup detection
> from kicking in... Maybe you can try starting the X server with
> -dumbSched to see if that gets things along any further, but in the end
> there's probably no way around figuring out what causes the lockup and
> fixing that anyway.

I have an old AGP box that locks with 600g + agpgart - It used to give 
GPU lockup to dmesg/log, but (I only test it occasionally) it doesn't 
anymore. I can still sysrq OK.

I wonder if something changed in recent months in the drm/whatever code 
that has changed/blocked the logging.