https://bugs.freedesktop.org/show_bug.cgi?id=91278
--- Comment #32 from Andy Furniss adf.lists@gmail.com --- (In reply to Mathias Tillman from comment #31)
Small update: I have been able to run it for a total of 7 hours (2 + 2 + 3) without a hang on the latest drm-next-4.4-wip. Tried the latest drm-fixes-4.3 and it hung after about 30 minutes, so I definitely think there's something in 4.4 that fixes it. I will do a bisect to see if I can figure out what, more exactly, is the fix.
I'll try over the weekend - no locks so far.
Bisecting would be a pain for me as I managed to very long lucky runs previously, so wouldn't be able to easily call good.
I notice that enable_scheduler is now on by default, maybe flipping that would be quicker than bisect. Long ago I did try some older kernel with that enabled and though it didn't fix IIRC it took longer to lock than was normal at that time.