I saw similar issue when adding a 2nd screen to my 15.10 systemd + lightdm system, which had been happy with single screen. Also happy when systemd not used, even with 2 displays
Booted OK, but on resume from suspend (usually after going to lock screen) things were completely hung with per-second repeats of Dec 1 01:13:00 grunt kernel: [ 591.465083] nouveau E[compiz[5704]] fail ttm_va lidate Dec 1 01:13:00 grunt kernel: [ 591.465092] nouveau E[compiz[5704]] validating bo list Dec 1 01:13:00 grunt kernel: [ 591.465118] nouveau E[compiz[5704]] validate: -12 ... Nouveau is kernel driver, but the issue seemed to come from compiz paging. Yet compiz behavior is directed by its clients. When I noticed 'service lightdm status' had warnings about libpam_kwallet5, I looked at how that was used. Found I had no pam-kwallet5, because I don't use kde/plasma. I did have kwallet4, which gnome depends on. So what was bitching about kwallet5??? Still not sure where the missing dpkg dependency on pam-kwallet5 should go, but it's definately needed -- I added pam-kwallet5 over ssh session and the hung displays immediately came back to life. Lightdm's pam usage of kwallet5 is allegedly always optional, as in /etc/pam.d/lightdm-greeter:132:auth optional pam_kwallet5.so /etc/pam.d/lightdm-greeter:543:session optional pam_kwallet5.so auto_start /etc/pam.d/lightdm:223:auth optional pam_kwallet5.so /etc/pam.d/lightdm:675:session optional pam_kwallet5.so auto_start But some defect makes it mandatory in a multi-display systemd setup. Perhaps it's a sequential overspecification in restore logic revealed by multi-display and system event handling. Don't yet understand, but adding the allegedly optional pam-kwallet5 fixed it -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1434396 Title: Xserver does not start or freezes with systemd + lightdm To manage notifications about this bug go to: https://bugs.launchpad.net/lightdm/+bug/1434396/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
