The nouveau isn't threadsafe and the Qt renderer uses threaded GL by default.
We don't know if Mir's default renderer would also exhibit the same issue when running multimonitor. (The Mir renderer uses a thread per monitor, but this is a simpler usage pattern than Qt and may not manifest problems.) ** Changed in: mir Status: Triaged => Incomplete ** Changed in: mir Importance: High => Undecided ** Changed in: mir (Ubuntu) Status: Triaged => Incomplete ** Changed in: mir (Ubuntu) Importance: High => Undecided ** Changed in: canonical-devices-system-image Assignee: Stephen M. Webb (bregma) => (unassigned) -- 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/1553328 Title: Mir/Unity8/USC crashes/freezes on nouveau (nv50) in pushbuf_kref() especially with multiple monitors, webbrowser-app or system settings To manage notifications about this bug go to: https://bugs.launchpad.net/canonical-devices-system-image/+bug/1553328/+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