https://bugzilla.kernel.org/show_bug.cgi?id=85421
--- Comment #16 from Hin-Tak Leung htl10@users.sourceforge.net --- I finally had a lock-up with mesa 10.2.9. Looking at the logs, I have had a fair number of GPU faults which I did not notice, briefly for a few seconds about 4 hours before an extended period of 1/2 hour of such faults. I believe in the 2nd period I was watching a video with mplayer. (the first period might be a trial run of the same video). I suspended the machine to RAM, then on waking up, the screen flashed a few times between black and the last desktop look, with some corruption in the desktop look; the mouse is still responsive to movement but clicking no longer works, nor keyboard (trying to switch to a vt to shutdown/reboot, did not respond).
Anyway, I am onto mesa 10.3.4 now, which includes http://cgit.freedesktop.org/mesa/mesa/commit/?id=ae4536b4f71cbe76230ea7edc7e... . I hope this get fixed properly though, since the change looks like it just band-aided over something.