i915 freakout with latest 3.7 git

[Lekensteyn]

On Tuesday 04 December 2012 22:08:45 Heinz Diehl wrote:
> Ok, but in comment 11 in the same thread you mention that reverting
> this patch didn't fix the issue for you:
> 
> "Reverting that commit on top of 3.7-rc4 did not fix the hang issue."
The bisected commit was from between rc2 and rc3:
$ git describe 504c7267a1e84b157cbd7e9c1b805e1bc0c2c846
v3.6-rc2-88-g504c726
The fact that reverting that commit does not help implies that some commits 
thereafter also expose the bug.

> > i915.i915_enable_rc6=0 worked for me, if it does not work for you, then
> > you  probably hit another bug.
> 
> I have now i915.i915_enable_rc6=0 in grub.cfg and disabled the XFCE
> compositor. Now I'm trying to hit the bug again...
Do you have a reliable reproduce method? As you can see in the linked bug it 
was caused by relatively low memory pressure combined with high I/O (caching? 
delays? Who knows).

> A shot in the dark: could it be that all the machines wich encounter
> this hang have nvidia's optimus? Mine has. Could that somehow be
> related? (I'm by no means a programmer or a kernel hacker..).
It is unlikely that Optimus has anything to do with this.

Peter