black screen with "_" with enabled Wayland

[Mateusz Łącki]

After installing 22.10 beta, the gdm3 does not start properly. This happens only if in /etc/gdm3/custom.conf :

[daemon]
# Uncomment the line below to force the login screen to use Xorg
WaylandEnable=false
(...)

The line with WaylandEnable is commented out or set explicitly to WaylandEnable=true.
Then the system boots into the state when the screen is black, there is underscore "_" present in top left corner, one can ssh into the system, but keyboard input is ignored. With WaylandEnable=false the system is fully functional. Before the update, with WaylandEnable=true the have been no such problems.

I will attach any logs upon request. Below those that I thought of on myself:

Description: Ubuntu Kinetic Kudu (development branch)
Release: 22.10

gdm3:
  Installed: 42.0-1ubuntu7
  Candidate: 42.0-1ubuntu7
  Version table:
 *** 42.0-1ubuntu7 500
        500 http://archive.ubuntu.com/ubuntu kinetic/main amd64 Packages
        100 /var/lib/dpkg/status

Note that the system logs have been created as follows:
1) I booted the machine with WaylandEnable=true,
2) I sshd into the machine, changed WaylandEnable to false, and restart gdm3
so the last few entries will likely describe the proper "x11" launch of the gdm3.

cat /var/log/syslog | grep -i gdm3
is attached as gdm.log

ProblemType: Bug
DistroRelease: Ubuntu 22.10
Package: gdm3 42.0-1ubuntu7 [modified: lib/udev/rules.d/61-gdm.rules]
ProcVersionSignature: Ubuntu 5.19.0-18.18-generic 5.19.7
Uname: Linux 5.19.0-18-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.23.0-0ubuntu2
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: ubuntu:GNOME
Date: Fri Oct 7 10:29:20 2022
EcryptfsInUse: Yes
SourcePackage: gdm3
UpgradeStatus: Upgraded to kinetic on 2022-10-06 (0 days ago)
mtime.conffile..etc.apport.crashdb.conf: 2021-05-03T18:07:38.595923
mtime.conffile..etc.gdm3.custom.conf: 2022-10-07T10:28:39.739012

[Daniel van Vugt (vanvugt)]

It looks like the attached log is from Xorg. Could you please collect a log from the attempted Wayland startup?

If it was the previous boot then run:

  journalctl -b-1 > prevboot.txt

Please also run:

  lspci -k > lspci.txt

and attach both files here.

[Mateusz Łącki (mateusz-lacki)]

The log is from /var/log/syslog but it contains more information than usual as I have turned on:
[debug]
# Uncomment the line below to turn on debugging
# More verbose logs
# Additionally lets the X server dump core if it crashes
Enable=true

in /etc/gdm3/custom.conf.

I attach both requested files

[Mateusz Łącki (mateusz-lacki)]

and lspci.

[Mateusz Łącki (mateusz-lacki)]

Today there has been a gdm3 update. There is progress with "WaylandEnable=true" the gdm3 actually starts, but only "Ubuntu" session can be logged in "Ubuntu on Wayland" ends on "blinking underscore". This is still a regression as Wayland used to work on 22.04. Though most likely this now goes to the "mutter" not gdm3.

[Daniel van Vugt (vanvugt)]

OK let's move to bug 1992285.