Further details: mouse cursor is briefly visible just prior to the black (login) screen. GDM does show up on the display, but in too big a resolution, so that I only get some of the grey background visible on screen and still have to log in blindly.
It occurred to me that with lightdm, the symptom appears as I would expect if it failed to do monitor detection properly and thinks it's displaying the login screen on the (broken) internal display only. Well, apart from the funky "login screen desktop background" phenomenon (which could be a separate issue though). (Just to be clear: this same combination of broken internal + working external display did display the login screen correctly on the external one in Precise.) -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to unity-greeter in Ubuntu. https://bugs.launchpad.net/bugs/1254319 Title: Black screen instead of login screen; input works Status in “unity-greeter” package in Ubuntu: New Bug description: This is a laptop with a broken internal display ("LVDS1" in xrandr output), and therefore connected to a working external LCD ("VGA1"). After upgrading from Precise to Trusty, boot ends with a black screen (on the external display). The greeter sound effect is played. Typing my password (I'm the sole user) does log me in, and brings up the desktop on the display. So the login functionality is there, just the visuals are missing. And they do flash by (corrupted) when the desktop is loading; if I set automatic login for myself, I get a desktop with the login screen as the background image (I'll attach a screenshot). There are existing, similar reports but all with subtle differences from this (such as Bug #1252748, where the user only gets black screen half the time) or too vague for me to claim to be the same issue with certainty (such as Bug #1242213). A lightdm restart (such as in Bug #969489) doesn't fix this (i.e. black screen still after lightdm restart). I'm not sure whether this is a lightdm issue or a unity-greeter one, so my reporting this against the latter is just a guess. ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: unity-greeter 14.04.1-0ubuntu1 ProcVersionSignature: Ubuntu 3.12.0-4.10-generic 3.12.1 Uname: Linux 3.12.0-4-generic x86_64 ApportVersion: 2.12.7-0ubuntu1 Architecture: amd64 CurrentDesktop: Unity Date: Sat Nov 23 20:53:43 2013 InstallationDate: Installed on 2012-05-25 (547 days ago) InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425) SourcePackage: unity-greeter UpgradeStatus: Upgraded to trusty on 2013-11-17 (6 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/unity-greeter/+bug/1254319/+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
