GDM broken after switching Gnome session to X11 once

[c4em]

Describe the bug Both X11 and Wayland Gnome sessions boot in to a black screen and spam journalctl repeatedly with these lines until gdm is stopped: Mär 28 16:03:35 silverblue /usr/libexec/gdm-wayland-session[2116]: invalid input: Mär 28 16:15:23 silverblue /usr/libexec/gdm-x-session[3104]: invalid input:

To Reproduce Please describe the steps needed to reproduce the bug:

1. Use the Gnome Wayland session
2. Log out
3. Select the Gnome X11 session
4. Log in

OS version:

State: idle
BootedDeployment:
● fedora:fedora/40/x86_64/silverblue
                  Version: 40.20240328.n.0 (2024-03-28T08:09:28Z)
               BaseCommit: f726d0be3361a42a8ac175b08851de67a2d97c9c01ee130a3abcd32720120f9c
             GPGSignature: Valid signature by 115DF9AEF857853EE8445D0A0727707EA15B79CC
      RemovedBasePackages: firefox firefox-langpacks 124.0.1-2.fc40
                           gnome-disk-utility 46.0-1.fc40 gnome-system-monitor 46~rc-1.fc40
                           gnome-terminal-nautilus gnome-terminal 3.50.1-6.fc40
                           gnome-tour 45.0-5.fc40 toolbox 0.0.99.5-8.fc40
                           yelp 2:42.2-5.fc40
          LayeredPackages: akmod-nvidia distrobox langpacks-de xorg-x11-drv-nvidia

I've also tried without any modifications of the base image

State: idle
BootedDeployment:
● fedora:fedora/40/x86_64/silverblue
                  Version: 40.20240328.n.0 (2024-03-28T08:09:28Z)
                   Commit: f726d0be3361a42a8ac175b08851de67a2d97c9c01ee130a3abcd32720120f9c
             GPGSignature: Valid signature by 115DF9AEF857853EE8445D0A0727707EA15B79CC

This problem was initially observed with the Fedora 39 image, I updated to 40 in hopes of maybe resolving this issue through that but it did not help.

Additional context

Here's the dmesg output when trying to launch the Wayland session: dmesg.log And here is the output of journalctl -xb: journalctl.log

I've also tried hunting down any cache or config directories of gdm and removing them. This also did not resolve the issue.

[chrisawi]

Mär 28 16:03:35 silverblue /usr/libexec/gdm-wayland-session[2116]: [a] | silverblue | fedora:fedora/40/x86_64/silverblue
Mär 28 16:03:35 silverblue /usr/libexec/gdm-wayland-session[2116]: [b] | devel | docker.io/library/archlinux:latest
Mär 28 16:03:35 silverblue /usr/libexec/gdm-wayland-session[2116]: [c] | devel-stable | docker.io/library/debian:latest
Mär 28 16:03:35 silverblue /usr/libexec/gdm-wayland-session[2116]: [d] | general | docker.io/library/archlinux:latest

Any idea what that output is from? Distrobox? And why is GDM seemingly running that instead of gnome-session?

Can you test with a new user account?

It might be helpful to enable GDM debug logging in /etc/gdm/custom.conf.

P.S. The journalctl -x flag just adds noise when sharing logs with others (and is pretty useless in general, imho).

[c4em]

Any idea what that output is from? Distrobox? And why is GDM seemingly running that instead of gnome-session?

Oh, that's a script I added to to my .bash_profile as a convenience to pick the environment to enter whenever I start a new shell session. I didn't know that this could prevent gdm from launching sessions, my bad, I've now added a check to ensure that it's actually being called inside of a terminal emulator and this fixed it. I couldn't find the part you pointed out in the logs, otherwise I would've caught on sooner, thank you for your help. Closing this, as this was caused by user error, sorry.

P.S. The journalctl -x flag just adds noise when sharing logs with others (and is pretty useless in general, imho).

And thank you for the advice, I'll remember it for next time.