For what its worth, running 3.13.7 greatly mitigates this bug, to where the dead time is barely noticeable. It happened three times in short order here and I didn't notice any of them:
[ 4562.551141] [drm:ring_stuck] *ERROR* Kicking stuck semaphore on render ring [ 4582.530028] [drm:ring_stuck] *ERROR* Kicking stuck semaphore on render ring [ 4633.476199] [drm:ring_stuck] *ERROR* Kicking stuck semaphore on render ring -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to mesa in Ubuntu. https://bugs.launchpad.net/bugs/1140716 Title: [regression] 3.5.0-26-generic and 3.2.0-39-generic GPU hangs on Sandybridge To manage notifications about this bug go to: https://bugs.launchpad.net/dri/+bug/1140716/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : [email protected] Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp

