https://bugzilla.kernel.org/show_bug.cgi?id=87791
--- Comment #3 from aCaB acab@digitalfuture.it --- (In reply to Alex Deucher from comment #2)
This sounds like a mesa regression rather than a kernel driver bug. Can you bisect mesa?
I understand mesa may be sending crap to the kernel space but that doesn't sound like a good reason to deref a NULL.
As for bisecting mesa, I am certainly willing to do that but I need a reliable way to trigger the lockup rather than just log in and wait for it to occour. Will see if I get more hints over then next few days.