Lightdm/xfce doesn't start anymore | Unable to identify cause

User Support
1

What I did: Casual dom0 update and upgrading my nvidia (official) driver manually.

What happens: Black screen after booting, only access to tty

Why I am confused: Weirdly enough my iGPU is affected too and sddm works perfectly fine. Sddm → Xfce4 doesn’t work too.

What I tried: Reinstalling lightdm multiple times, resetting my X11 config file, trying to understand my journalctl, uninstalling my nvidia driver, researching if someone experiences the same issues currently.

Why I need help: I am just out of ideas what could cause the issue. Might the lightdm packages be broken? In this case I would not be the only one affected. Do you have any ideas?

2

If journalctl is fine, see logs in /var/log/Xorg.*.log

3

Journalctl is not fine, it says that it fails but without giving a reason. There is nothing reported in the xorg logs.

4

What does it say?

5

I don’t think this is helpful at all.

Nov 22 12:19:06 dom0 systemd[1]: Starting lightdm.service - Light Display Manager...
░░ Subject: A start job for unit lightdm.service has begun execution
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has begun execution.
░░ 
░░ The job identifier is 319.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Main process exited, code=exited, status=1/FAILURE
░░ Subject: Unit process exited
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ An ExecStart= process belonging to unit lightdm.service has exited.
░░ 
░░ The process' exit code is 'exited' and its exit status is 1.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Failed with result 'exit-code'.
░░ Subject: Unit failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ The unit lightdm.service has entered the 'failed' state with result 'exit-code'.
Nov 22 12:19:06 dom0 systemd[1]: Failed to start lightdm.service - Light Display Manager.
░░ Subject: A start job for unit lightdm.service has failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has finished with a failure.
░░ 
░░ The job identifier is 319 and the job result is failed.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Scheduled restart job, restart counter is at 1.
░░ Subject: Automatic restarting of a unit has been scheduled
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ Automatic restarting of the unit lightdm.service has been scheduled, as the result for
░░ the configured Restart= setting for the unit.
Nov 22 12:19:06 dom0 systemd[1]: Stopped lightdm.service - Light Display Manager.
░░ Subject: A stop job for unit lightdm.service has finished
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A stop job for unit lightdm.service has finished.
░░ 
░░ The job identifier is 2653 and the job result is done.
Nov 22 12:19:06 dom0 systemd[1]: Starting lightdm.service - Light Display Manager...
░░ Subject: A start job for unit lightdm.service has begun execution
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has begun execution.
░░ 
░░ The job identifier is 2653.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Main process exited, code=exited, status=1/FAILURE
░░ Subject: Unit process exited
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ An ExecStart= process belonging to unit lightdm.service has exited.
░░ 
░░ The process' exit code is 'exited' and its exit status is 1.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Failed with result 'exit-code'.
░░ Subject: Unit failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ The unit lightdm.service has entered the 'failed' state with result 'exit-code'.
Nov 22 12:19:06 dom0 systemd[1]: Failed to start lightdm.service - Light Display Manager.
░░ Subject: A start job for unit lightdm.service has failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has finished with a failure.
░░ 
░░ The job identifier is 2653 and the job result is failed.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Scheduled restart job, restart counter is at 2.
░░ Subject: Automatic restarting of a unit has been scheduled
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ Automatic restarting of the unit lightdm.service has been scheduled, as the result for
░░ the configured Restart= setting for the unit.
Nov 22 12:19:06 dom0 systemd[1]: Stopped lightdm.service - Light Display Manager.
░░ Subject: A stop job for unit lightdm.service has finished
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A stop job for unit lightdm.service has finished.
░░ 
░░ The job identifier is 2782 and the job result is done.
Nov 22 12:19:06 dom0 systemd[1]: Starting lightdm.service - Light Display Manager...
░░ Subject: A start job for unit lightdm.service has begun execution
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has begun execution.
░░ 
░░ The job identifier is 2782.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Main process exited, code=exited, status=1/FAILURE
░░ Subject: Unit process exited
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ An ExecStart= process belonging to unit lightdm.service has exited.
░░ 
░░ The process' exit code is 'exited' and its exit status is 1.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Failed with result 'exit-code'.
░░ Subject: Unit failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ The unit lightdm.service has entered the 'failed' state with result 'exit-code'.
Nov 22 12:19:06 dom0 systemd[1]: Failed to start lightdm.service - Light Display Manager.
░░ Subject: A start job for unit lightdm.service has failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has finished with a failure.
░░ 
░░ The job identifier is 2782 and the job result is failed.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Scheduled restart job, restart counter is at 3.
░░ Subject: Automatic restarting of a unit has been scheduled
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ Automatic restarting of the unit lightdm.service has been scheduled, as the result for
░░ the configured Restart= setting for the unit.
Nov 22 12:19:06 dom0 systemd[1]: Stopped lightdm.service - Light Display Manager.
░░ Subject: A stop job for unit lightdm.service has finished
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A stop job for unit lightdm.service has finished.
░░ 
░░ The job identifier is 2911 and the job result is done.
Nov 22 12:19:06 dom0 systemd[1]: Starting lightdm.service - Light Display Manager...
░░ Subject: A start job for unit lightdm.service has begun execution
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has begun execution.
░░ 
░░ The job identifier is 2911.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Main process exited, code=exited, status=1/FAILURE
░░ Subject: Unit process exited
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ An ExecStart= process belonging to unit lightdm.service has exited.
░░ 
░░ The process' exit code is 'exited' and its exit status is 1.
Nov 22 12:19:06 dom0 systemd[1]: lightdm.service: Failed with result 'exit-code'.
░░ Subject: Unit failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ The unit lightdm.service has entered the 'failed' state with result 'exit-code'.
Nov 22 12:19:06 dom0 systemd[1]: Failed to start lightdm.service - Light Display Manager.
░░ Subject: A start job for unit lightdm.service has failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has finished with a failure.
░░ 
░░ The job identifier is 2911 and the job result is failed.
Nov 22 12:19:07 dom0 systemd[1]: lightdm.service: Scheduled restart job, restart counter is at 4.
░░ Subject: Automatic restarting of a unit has been scheduled
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ Automatic restarting of the unit lightdm.service has been scheduled, as the result for
░░ the configured Restart= setting for the unit.
Nov 22 12:19:07 dom0 systemd[1]: Stopped lightdm.service - Light Display Manager.
░░ Subject: A stop job for unit lightdm.service has finished
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A stop job for unit lightdm.service has finished.
░░ 
░░ The job identifier is 3040 and the job result is done.
Nov 22 12:19:07 dom0 systemd[1]: Starting lightdm.service - Light Display Manager...
░░ Subject: A start job for unit lightdm.service has begun execution
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has begun execution.
░░ 
░░ The job identifier is 3040.
Nov 22 12:19:07 dom0 systemd[1]: lightdm.service: Main process exited, code=exited, status=1/FAILURE
░░ Subject: Unit process exited
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ An ExecStart= process belonging to unit lightdm.service has exited.
░░ 
░░ The process' exit code is 'exited' and its exit status is 1.
Nov 22 12:19:07 dom0 systemd[1]: lightdm.service: Failed with result 'exit-code'.
░░ Subject: Unit failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ The unit lightdm.service has entered the 'failed' state with result 'exit-code'.
Nov 22 12:19:07 dom0 systemd[1]: Failed to start lightdm.service - Light Display Manager.
░░ Subject: A start job for unit lightdm.service has failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has finished with a failure.
░░ 
░░ The job identifier is 3040 and the job result is failed.
Nov 22 12:19:07 dom0 systemd[1]: lightdm.service: Scheduled restart job, restart counter is at 5.
░░ Subject: Automatic restarting of a unit has been scheduled
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ Automatic restarting of the unit lightdm.service has been scheduled, as the result for
░░ the configured Restart= setting for the unit.
Nov 22 12:19:07 dom0 systemd[1]: Stopped lightdm.service - Light Display Manager.
░░ Subject: A stop job for unit lightdm.service has finished
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A stop job for unit lightdm.service has finished.
░░ 
░░ The job identifier is 3169 and the job result is done.
Nov 22 12:19:07 dom0 systemd[1]: lightdm.service: Start request repeated too quickly.
Nov 22 12:19:07 dom0 systemd[1]: lightdm.service: Failed with result 'exit-code'.
░░ Subject: Unit failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ The unit lightdm.service has entered the 'failed' state with result 'exit-code'.
Nov 22 12:19:07 dom0 systemd[1]: Failed to start lightdm.service - Light Display Manager.
░░ Subject: A start job for unit lightdm.service has failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
░░ 
░░ A start job for unit lightdm.service has finished with a failure.
░░ 
░░ The job identifier is 3169 and the job result is failed.
Nov 22 12:19:07 dom0 systemd[1]: lightdm.service: Triggering OnFailure= dependencies.
1 Like
6

Does it say anything in /var/log/lightdm/lightdm.log and /var/log/lightdm/x-*.log?

7

Thanks, we are closer!

[+0.00s] DEBUG: Logging to /var/log/lightdm/lightdm.log
[+0.00s] DEBUG: Starting Light Display Manager 1.32.0, UID=0 PID=6520
[+0.00s] DEBUG: Loading configuration dirs from /usr/share/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-backup-logs.conf
[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-disable-guest.conf
[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-minimum-vt.conf
[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-run-directory.conf
[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-session-wrapper.conf
[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-user-authority-in-system-dir.conf
[+0.00s] DEBUG: Loading configuration from /usr/share/lightdm/lightdm.conf.d/50-xserver-command.conf
[+0.00s] DEBUG: Loading configuration dirs from /usr/local/share/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration dirs from /etc/xdg/lightdm/lightdm.conf.d
[+0.00s] DEBUG: Loading configuration from /etc/lightdm/lightdm.conf
[+0.00s] DEBUG: Registered seat module local
[+0.00s] DEBUG: Registered seat module xremote
[+0.00s] DEBUG: Using D-Bus name org.freedesktop.DisplayManager
[+0.00s] DEBUG: Using cross-namespace EXTERNAL authentication (this will deadlock if server is GDBus < 2.73.3)
[+0.00s] DEBUG: _g_io_module_get_default: Found default implementation local (GLocalVfs) for ‘gio-vfs’
[+0.00s] DEBUG: Monitoring logind for seats
[+0.00s] DEBUG: New seat added from logind: seat0
[+0.00s] DEBUG: Seat seat0: Loading properties from config section Seat:*
[+0.00s] DEBUG: Seat seat0 has property CanMultiSession=no
[+0.00s] DEBUG: Seat seat0: Starting
[+0.00s] DEBUG: Seat seat0: Creating greeter session
[+0.00s] DEBUG: Seat seat0: Failed to find session configuration lightdm-greeter
[+0.00s] DEBUG: Seat seat0: Failed to create greeter session
[+0.00s] DEBUG: Failed to start seat: seat0
8

Worked! Found a fix! Though… There is a new ‘fun’ problem:

Windows of Qubes aren’t displayed, just Windows of dom0 work fine. The qubes themselves work.

9

What is the fix?

10

Great idea to post: Something uninstalled my greeter. Though why I have my new problem?

Dom0 even works perfectly fine… Other qubes won’t show up even if they clearly started and are all still functional.