GNOME Bugzilla – Bug 756051
Unable to start gnome wayland with VGEM kernel module compiled in
Last modified: 2015-10-05 06:50:53 UTC
When I try to launch "Gnome on Wayland" from GDM and I have compiled-in kernel module "VGEM", then I am unable to start the session. When VGEM module is not loaded or compiled as module and loaded, it starts fine. The relevant part of log is here: Oct 04 15:55:03 strix gnome-session[964]: Unrecoverable failure in required component gnome-shell-wayland.desktop Oct 04 15:55:03 strix gnome-session[964]: gnome-session[964]: WARNING: Application 'gnome-shell-wayland.desktop' killed by signal 5 Oct 04 15:55:03 strix gnome-session[964]: WARNING: Application 'gnome-shell-wayland.desktop' killed by signal 5 Oct 04 15:55:03 strix gnome-session[964]: (gnome-shell:982): mutter-ERROR **: Unable to initialize Clutter. Oct 04 15:55:03 strix gnome-session[964]: (gnome-shell:982): Clutter-CRITICAL **: Unable to initialize Clutter: drmModeGetResources failed Oct 04 15:55:03 strix gnome-session[964]: failed to load driver: vgem Oct 04 15:55:03 strix gnome-session[964]: gbm: Last dlopen error: /usr/lib64/dri/vgem_dri.so: cannot open shared object file: No such file or directory Oct 04 15:55:03 strix gnome-session[964]: gbm: failed to open any driver (search paths /usr/lib64/dri) Oct 04 15:55:03 strix gnome-session[964]: MESA-LOADER: could not get parent device Oct 04 15:55:03 strix /usr/libexec/gdm-wayland-session[961]: Successfully activated service 'org.gtk.vfs.Daemon' Oct 04 15:55:03 strix /usr/libexec/gdm-wayland-session[961]: Activating service name='org.gtk.vfs.Daemon' I don't have latest Gnome (I am at 3.16.x), but searching in commits have not revealed anything related.
vgem is a kms-sw (display only, no acceleration) driver, and should be supported by the kms_swrast_dri mesa driver. That fact that mesa bails after failing to load the non-existent vgem_dri driver is a mesa bug (or a configuration problem in the build system), but not a gnome shell issue. Please file a bug at Freedesktop under the mesa product, but please also check that your distro builds mesa with an enabled kms-swrast driver and either softpipe or llvmpipe.
Uh. I imagine what's happening is that we hardcode /dev/dri/card0, which is VGEM, and then there's another display driver, card1, which works fine. Because, as he says, "when VGEM isn't loaded, it works fine". It's likely fixed in 3.18 by https://git.gnome.org/browse/mutter/commit/?id=79f755bf0fa03eac3687184670c1f8142d3160a6 Reopening until the reporter says it's fixed.
Thank you, I was not able to find that bug or commit. It is definitely duplicate of that one. Reordering the /dev/dri/card* was exactly what worked. I was also looking for some setting how to select which GPU to use, but failed to find any. Thank you for your help and sorry for duplicate bug report. *** This bug has been marked as a duplicate of bug 753434 ***