It appears you have some unsupported graphics packages installed from the "Oibaf" PPA.
Please purge that PPA from your system and if you continue to have any problems after that then open a new bug. ** Changed in: xorg (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1825794 Title: Xorg freeze To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1825794/+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