[SOLVED] Display manager (LightDM) failing to load after reboot

jd88 · 2016-01-03 19:19:33

Had recently updated system, but had not rebooted in a few days. Reboot system this morning and LightDM is failing to load

journalctl shows the following:

*** (lightdm:709): CRITICAL **: session_get_login1_session_id: assertion 'session != NULL' failed

If I try to run lightdm-gtk-greeter I get the following message:

*** Message: Starting lightdm-gtk-greeter 2.0.1 (May 26 2015, 08:48:40)
*** Message: [Configuration] Reading file: /etc/lightdm/lightdm-gtk-greeter.conf
Unable to init server: Could not connect: Connection refused

(lightdm-gtk-greeter:835): Gtk-WARNING **: cannot open display:

Tried alternative display managers (slim, lxdm) and those also failed to start. Have also tried re-installing xorg, xf86-video-intel, lightdm, but no luck.

Last edited by jd88 (2016-01-05 04:31:23)

midixinga · 2016-01-04 01:01:44

did you try another user?

jd88 · 2016-01-05 04:31:07

Sorry if that wasn't clear, the DM was not loading and I was left with a blank screen. Could switch tty and login just fine.

Anyway, mucked things up too much and just ended up reinstalling.

0xADADA · 2016-03-22 01:47:45

Did you end up solving this problem? I'm in the same situation...

mrunion · 2016-03-22 12:05:55

Sounds like the OP just reinstalled to fix the issue.

0xADADA · 2016-03-22 13:27:02

mrunion wrote:

Sounds like the OP just reinstalled to fix the issue.

is that the accepted solution?

ewaller · 2016-03-22 14:44:17

0xADADA wrote:

is that the accepted solution?

Seems a bit extreme. Generally no.

Does Xorg work at all, or is it just the display manager that is having issues? I highly recommend disabling the display manager until you know it is not an Xorg problem. Once it is disabled, use startx to try stating Xorg and see what happens. Also, if you can post your Xorg.0.log file that would be helpful.

0xADADA · 2016-03-22 15:04:25

ewaller wrote:

0xADADA wrote:
is that the accepted solution?
Seems a bit extreme. Generally no.
Does Xorg work at all, or is it just the display manager that is having issues? I highly recommend disabling the display manager until you know it is not an Xorg problem. Once it is disabled, use startx to try stating Xorg and see what happens. Also, if you can post your Xorg.0.log file that would be helpful.

Lightdm.service is disabled. Currently, I just login on the virtual console, and then do startx to get into X. X starts without any problems.

Once in X, i can run `lightdm` in debug mode and it starts correctly. I can also run `lightdm-webkit2-greeter` and that works correctly.

If I run:
# systemctl start lightdm.service
the screen flickers, a cursor in the top left of the screen appears, and the whole system freezes. Cannot even change to a different TTY.

I get this in the logs:

-- Logs begin at Thu 2016-02-18 21:51:07 EST, end at Mon 2016-03-21 21:18:46 EDT. --
Mar 21 21:14:11 zizek sudo[12365]:      0xa : TTY=tty1 ; PWD=/home/0xa; USER=root ; COMMAND=/usr/bin/systemctl start lightdm
Mar 21 21:14:11 zizek sudo[12365]: pam_unix(sudo:session): session opened for user root by ron(uid=0)
Mar 21 21:14:11 zizek polkitd[13384]: Registered Authentication Agent for unix-process:12366:44140431 (system bus name :1.3715 [/usr/bin/pkttyagent --notify-fd 4 --fallback], object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US)
Mar 21 21:14:11 zizek systemd[1]: Starting Light Display Manager...
-- Subject: Unit lightdm.service has begun start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit lightdm.service has begun starting up.
Mar 21 21:14:11 zizek systemd[1]: Started Light Display Manager.
-- Subject: Unit lightdm.service has finished start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit lightdm.service has finished starting up.
-- 
-- The start-up result is done.
Mar 21 21:14:11 zizek lightdm[12372]: ** (lightdm:12372): WARNING **: Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.Accounts was not provided by any .service files
Mar 21 21:14:11 zizek polkitd[13384]: Unregistered Authentication Agent for unix-process:12366:44140431 (system bus name :1.3715, object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US) (disconnected from bus)
Mar 21 21:14:11 zizek sudo[12365]: pam_unix(sudo:session): session closed for user root
Mar 21 21:14:11 zizek lightdm[12372]: ** (lightdm:12372): CRITICAL **: session_get_login1_session_id: assertion 'session != NULL' failed

After that I need to press the power button, and the journalctl logs contain the powerdown events properly. It seems the screen becomes totally unresponsive.

There are plenty of other threads about this problem, but all of them end without resolution, or the user ends the thread by saying "I reinstalled and the problem went away". I'm hoping to actually solve this problem, and have it documented here for posterity

Last edited by 0xADADA (2017-01-22 17:28:32)

Arch Linux

#1 2016-01-03 19:19:33

[SOLVED] Display manager (LightDM) failing to load after reboot

#2 2016-01-04 01:01:44

Re: [SOLVED] Display manager (LightDM) failing to load after reboot

#3 2016-01-05 04:31:07

Re: [SOLVED] Display manager (LightDM) failing to load after reboot

#4 2016-03-22 01:47:45

Re: [SOLVED] Display manager (LightDM) failing to load after reboot

#5 2016-03-22 12:05:55

Re: [SOLVED] Display manager (LightDM) failing to load after reboot

#6 2016-03-22 13:27:02

Re: [SOLVED] Display manager (LightDM) failing to load after reboot

#7 2016-03-22 14:44:17

Re: [SOLVED] Display manager (LightDM) failing to load after reboot

#8 2016-03-22 15:04:25

Re: [SOLVED] Display manager (LightDM) failing to load after reboot

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