I hope this upstream change set will do the trick: https://www.virtualbox.org/changeset/62242
Re comment 11, I looked at Mesa to see how they were distinguishing client and server GL and applied that to my code (see comments in change set). To summarise the issue: the tricks that we were playing to prevent the X server from loading our GL libraries, which unlike Mesa are designed to be client only, were not working here, and the X server process was failing when our libraries tried to call a function (RTR3InitDll) in another library which gets loaded by clients but which the X server was not (not sure why). I refined the tricks by studying how Mesa handles detecting being loaded by the server (technically being loaded for use with GBM rather than with X11) and in addition got rid of the immediate dependency which was failing. Was that at all helpful? -- 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/1599775 Title: "low-graphics mode" in VirtualBox guest, but X server running Status in lightdm package in Ubuntu: New Bug description: I sometimes get the "low-graphics mode" message when starting an Ubuntu 16.04 virtual machine inside of VirtualBox (current development code trunk, somewhere past version 5.1 beta 3 and a debug build). When I switch to VT-7 I find the X server running without any visible issues (I am the upstream developer of the guest graphics drivers, so I have a reasonable but not infallible understanding of the X server). The virtual machine has Guest Additions installed, same vintage and also a debug build. Two screens are enabled as is 3D acceleration. The host system is also Ubuntu 16.04. I am still trying to work out what triggers the message, but in my last attempts a cold boot failed to produce it, while a clean reboot did, but only when the host system was not under load (under load as in building VirtualBox). Searching the lightdm log files led me to the message "CRITICAL **: session_get_login1_session_id: assertion 'session != NULL' failed", which in turn led me to this similar-looking Debian bug: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=814760 ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: lightdm 1.18.1-0ubuntu1 ProcVersionSignature: Ubuntu 4.4.0-28.47-generic 4.4.13 Uname: Linux 4.4.0-28-generic x86_64 ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 CurrentDesktop: Unity Date: Thu Jul 7 10:49:27 2016 InstallationDate: Installed on 2016-06-08 (28 days ago) InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) SourcePackage: lightdm UpgradeStatus: No upgrade log present (probably fresh install) IRC discussion at: https://irclogs.ubuntu.com/2016/07/07/%23ubuntu-devel.html#t07:52 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/1599775/+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
