I had something interesting happen with kernel 4.7 rc5 and mesa 12.1 git1591e66
The system would lock up, and the console would fill with the stalling ring
messages. But then it won't lock up and will recover somewhat. The game
wouldn't crash either, allowing me to exit it cleanly. Plasmashell would crash
though, and there is a lot of video corruption on the desktop afterwards until
the reboot. Happened two times in a row