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 Desktop Packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/1434396 Title: Xserver does not start or freezes with systemd + lightdm Status in Light Display Manager: Confirmed Status in lightdm package in Ubuntu: Triaged Bug description: After upgrading to (32bit) vivid I hadn't got any problem, but since a day (daily upgraded) booting results in a dialog saying low graphics mode and a dialog window about this. Choosing running in default mode causes to boot splash to be shown forever. if I choose exit to console, log in then service stop then start for lightdm, it works then though. Maybe is not Xserver bug, but the new init system (systemd) race condition of starting things, or such? ProblemType: Bug DistroRelease: Ubuntu 15.04 Package: xserver-xorg 1:7.7+7ubuntu4 ProcVersionSignature: Ubuntu 3.19.0-9.9-generic 3.19.1 Uname: Linux 3.19.0-9-generic i686 .tmp.unity.support.test.0: ApportVersion: 2.16.2-0ubuntu3 Architecture: i386 CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins' CompositorRunning: compiz CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0' CompositorUnredirectFSW: true CurrentDesktop: Unity Date: Fri Mar 20 07:35:37 2015 DistUpgraded: 2014-10-24 18:45:04,038 DEBUG enabling apt cron job DistroCodename: vivid DistroVariant: ubuntu DkmsStatus: virtualbox, 4.3.26, 3.19.0-9-generic, i686: installed ExtraDebuggingInterest: Yes GraphicsCard: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0116] (rev 09) (prog-if 00 [VGA controller]) Subsystem: Lenovo Device [17aa:21dd] InstallationDate: Installed on 2012-03-03 (1111 days ago) InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release i386 (20110427.1) MachineType: LENOVO 5016NW6 ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.19.0-9-generic root=UUID=8df578aa-47e3-483f-b694-bf7effd24b7d ro i915.semaphores=0 quiet splash vt.handoff=7 SourcePackage: xorg UpgradeStatus: Upgraded to vivid on 2014-10-24 (146 days ago) dmi.bios.date: 11/04/2011 dmi.bios.vendor: LENOVO dmi.bios.version: 8GET38WW (1.15 ) dmi.board.name: 5016NW6 dmi.board.vendor: LENOVO dmi.board.version: Not Available dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvr8GET38WW(1.15):bd11/04/2011:svnLENOVO:pn5016NW6:pvrThinkPadL520:rvnLENOVO:rn5016NW6:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 5016NW6 dmi.product.version: ThinkPad L520 dmi.sys.vendor: LENOVO version.compiz: compiz 1:0.9.12.1+15.04.20150303-0ubuntu1 version.libdrm2: libdrm2 2.4.59-0ubuntu1 version.libgl1-mesa-dri: libgl1-mesa-dri 10.5.0-0ubuntu1 version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx 10.5.0-0ubuntu1 version.xserver-xorg-core: xserver-xorg-core 2:1.17.1-0ubuntu3 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.9.0-1ubuntu2 version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.5.0-1ubuntu2 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917-1~exp1ubuntu2build1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.11-1ubuntu2build1 xserver.bootTime: Fri Mar 20 07:25:51 2015 xserver.configfile: default xserver.errors: xserver.logfile: /var/log/Xorg.0.log xserver.outputs: product id 9196 vendor AUO xserver.version: 2:1.17.1-0ubuntu3 To manage notifications about this bug go to: https://bugs.launchpad.net/lightdm/+bug/1434396/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
