Public bug reported: Logging in after a fresh boot works fine. Subsequently, after locking the screen (either Super + L or allow to auto-lock) and letting the screen turn off automatically, then attempting to wake the machine, only a black screen and the mouse cursor are visible. The desktop and authentication prompt do not re-appear, and though the mouse cursor moves, the machine doesn't respond to keyboard entry except to switch to a virtual console with Ctrl + Alt + 1 (2, 3, etc). From there it's possible to reboot or kill -HUP lightdm, but in either case, the active Unity login session is lost. I've check various log files, including /var/log/lightdm/* but haven't noticed any obvious culprits.
This started after the following system updates on 2017-07-25 (/var/log/apt/history.log): Start-Date: 2017-07-25 08:32:14 Commandline: apt upgrade Requested-By: myusername (1000) Upgrade: libfwup0:amd64 (0.5-2ubuntu4, 0.5-2ubuntu5), unity-control-center-faces:amd64 (15.04.0+16.04.20160705-0ubuntu1, 15.04.0+16.04.20170214-0ubuntu1), linux-libc-dev:amd64 (4.4.0-83.106, 4.4.0-87.110), xserver-common:amd64 (2:1.18.4-0ubuntu0.2, 2:1.18.4-0ubuntu0.3), libgtk2.0-bin:amd64 (2.24.30-1ubuntu1, 2.24.30-1ubuntu1.16.04.1), imagemagick:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), libsystemd0:amd64 (229-4ubuntu17, 229-4ubuntu19), libmagickwand-6.q16-2:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), libgail-common:amd64 (2.24.30-1ubuntu1, 2.24.30-1ubuntu1.16.04.1), libgtk2.0-0:amd64 (2.24.30-1ubuntu1, 2.24.30-1ubuntu1.16.04.1), coreutils:amd64 (8.25-2ubuntu2, 8.25-2ubuntu3~16.04), udev:amd64 (229-4ubuntu17, 229-4ubuntu19), libepoxy0:amd64 (1.3.1-1ubuntu0.16.04.1, 1.3.1-1ubuntu0.16.04.2), libgail18:amd64 (2.24.30-1ubuntu1, 2.24.30-1ubuntu1.16.04.1), fwupdate:amd64 (0.5-2ubuntu4, 0.5-2ubuntu5), libudev1:amd64 (229-4ubuntu17, 229-4ubuntu19), unity-control-center:amd6 4 (15.04.0+16.04.20160705-0ubuntu1, 15.04.0+16.04.20170214-0ubuntu1), imagemagick-6.q16:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), libmagickcore-6.q16-2-extra:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), systemd-sysv:amd64 (229-4ubuntu17, 229-4ubuntu19), session-shortcuts:amd64 (1.2, 1.2ubuntu0.16.04.1), libpam-systemd:amd64 (229-4ubuntu17, 229-4ubuntu19), systemd:amd64 (229-4ubuntu17, 229-4ubuntu19), libmagickcore-6.q16-2:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), libgtk2.0-common:amd64 (2.24.30-1ubuntu1, 2.24.30-1ubuntu1.16.04.1), xserver-xorg-core-hwe-16.04:amd64 (2:1.18.4-1ubuntu6.1~16.04.1, 2:1.18.4-1ubuntu6.1~16.04.2), libunity-control-center1:amd64 (15.04.0+16.04.20160705-0ubuntu1, 15.04.0+16.04.20170214-0ubuntu1), imagemagick-common:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), fwupdate-signed:amd64 (1.11+0.5-2ubuntu4, 1.11.1+0.5-2ubuntu5) End-Date: 2017-07-25 08:34:11 ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: lightdm 1.18.3-0ubuntu1.1 ProcVersionSignature: Ubuntu 4.10.0-27.30~16.04.2-generic 4.10.17 Uname: Linux 4.10.0-27-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.10 Architecture: amd64 CurrentDesktop: Unity Date: Wed Jul 26 12:43:23 2017 EcryptfsInUse: Yes InstallationDate: Installed on 2017-05-19 (68 days ago) InstallationMedia: Ubuntu 16.04.2 LTS "Xenial Xerus" - Release amd64 (20170215.2) SourcePackage: lightdm UpgradeStatus: No upgrade log present (probably fresh install) ** Affects: lightdm (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug third-party-packages xenial -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to lightdm in Ubuntu. https://bugs.launchpad.net/bugs/1706760 Title: lightdm/login session fails to resume after display is locked and goes to black Status in lightdm package in Ubuntu: New Bug description: Logging in after a fresh boot works fine. Subsequently, after locking the screen (either Super + L or allow to auto-lock) and letting the screen turn off automatically, then attempting to wake the machine, only a black screen and the mouse cursor are visible. The desktop and authentication prompt do not re-appear, and though the mouse cursor moves, the machine doesn't respond to keyboard entry except to switch to a virtual console with Ctrl + Alt + 1 (2, 3, etc). From there it's possible to reboot or kill -HUP lightdm, but in either case, the active Unity login session is lost. I've check various log files, including /var/log/lightdm/* but haven't noticed any obvious culprits. This started after the following system updates on 2017-07-25 (/var/log/apt/history.log): Start-Date: 2017-07-25 08:32:14 Commandline: apt upgrade Requested-By: myusername (1000) Upgrade: libfwup0:amd64 (0.5-2ubuntu4, 0.5-2ubuntu5), unity-control-center-faces:amd64 (15.04.0+16.04.20160705-0ubuntu1, 15.04.0+16.04.20170214-0ubuntu1), linux-libc-dev:amd64 (4.4.0-83.106, 4.4.0-87.110), xserver-common:amd64 (2:1.18.4-0ubuntu0.2, 2:1.18.4-0ubuntu0.3), libgtk2.0-bin:amd64 (2.24.30-1ubuntu1, 2.24.30-1ubuntu1.16.04.1), imagemagick:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), libsystemd0:amd64 (229-4ubuntu17, 229-4ubuntu19), libmagickwand-6.q16-2:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), libgail-common:amd64 (2.24.30-1ubuntu1, 2.24.30-1ubuntu1.16.04.1), libgtk2.0-0:amd64 (2.24.30-1ubuntu1, 2.24.30-1ubuntu1.16.04.1), coreutils:amd64 (8.25-2ubuntu2, 8.25-2ubuntu3~16.04), udev:amd64 (229-4ubuntu17, 229-4ubuntu19), libepoxy0:amd64 (1.3.1-1ubuntu0.16.04.1, 1.3.1-1ubuntu0.16.04.2), libgail18:amd64 (2.24.30-1ubuntu1, 2.24.30-1ubuntu1.16.04.1), fwupdate:amd64 (0.5-2ubuntu4, 0.5-2ubuntu5), libudev1:amd64 (229-4ubuntu17, 229-4ubuntu19), unity-control-center:am d64 (15.04.0+16.04.20160705-0ubuntu1, 15.04.0+16.04.20170214-0ubuntu1), imagemagick-6.q16:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), libmagickcore-6.q16-2-extra:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), systemd-sysv:amd64 (229-4ubuntu17, 229-4ubuntu19), session-shortcuts:amd64 (1.2, 1.2ubuntu0.16.04.1), libpam-systemd:amd64 (229-4ubuntu17, 229-4ubuntu19), systemd:amd64 (229-4ubuntu17, 229-4ubuntu19), libmagickcore-6.q16-2:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), libgtk2.0-common:amd64 (2.24.30-1ubuntu1, 2.24.30-1ubuntu1.16.04.1), xserver-xorg-core-hwe-16.04:amd64 (2:1.18.4-1ubuntu6.1~16.04.1, 2:1.18.4-1ubuntu6.1~16.04.2), libunity-control-center1:amd64 (15.04.0+16.04.20160705-0ubuntu1, 15.04.0+16.04.20170214-0ubuntu1), imagemagick-common:amd64 (8:6.8.9.9-7ubuntu5.7, 8:6.8.9.9-7ubuntu5.8), fwupdate-signed:amd64 (1.11+0.5-2ubuntu4, 1.11.1+0.5-2ubuntu5) End-Date: 2017-07-25 08:34:11 ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: lightdm 1.18.3-0ubuntu1.1 ProcVersionSignature: Ubuntu 4.10.0-27.30~16.04.2-generic 4.10.17 Uname: Linux 4.10.0-27-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.10 Architecture: amd64 CurrentDesktop: Unity Date: Wed Jul 26 12:43:23 2017 EcryptfsInUse: Yes InstallationDate: Installed on 2017-05-19 (68 days ago) InstallationMedia: Ubuntu 16.04.2 LTS "Xenial Xerus" - Release amd64 (20170215.2) SourcePackage: lightdm UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1706760/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp