This issue appears to be an upstream bug, since you tested the latest upstream kernel. Would it be possible for you to open an upstream bug report[0]? That will allow the upstream Developers to examine the issue, and may provide a quicker resolution to the bug.
Please follow the instructions on the wiki page[0]. The first step is to email the appropriate mailing list. If no response is received, then a bug may be opened on bugzilla.kernel.org. Once this bug is reported upstream, please add the tag: 'kernel-bug- reported-upstream'. ** Changed in: linux (Ubuntu) Status: Confirmed => Triaged -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-nouveau in Ubuntu. https://bugs.launchpad.net/bugs/1191426 Title: logout is slow, profiling reveals lots of CPU time in nouveau_connector_detect To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1191426/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp