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mascip

Member

Registered: 2015-02-10

Posts: 29

Problem with lightdm turned into problem with X server, maybe...

Hi all,

yesterday for the first time, I entered my password in the lightdm Login manager and it didn't let me in. It would let me in when I entered the root password though.
So I entered as root, and disabled lightdm:

systemctl disable lightdm

After that the computer started normally, asked for my username and password, and then I did

startx

which worked and opened the graphical interface.

After that I installed gdm, then changed my mind and removed it (I think I did <code>pacman -R gdm</code>), then installed it again.
I think during one of these operations I forgot that it was dealing with gdm and turned off the computer, while it might still have been installing or removing. Then I removed and re-installed gdm, just in case.

Now at boot I get this and then it's all blocked:

[    6.574791] [drm:intel_set_cpu_fifo_underrun_reporting [i915]] *ERROR* uncleared fifo underrun on pipe B
[    6.574820] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun
[    6.574859] [drm:intel_set_pch_fifo_underrun_reporting [i915]] *ERROR* uncleared pch fifo underrun on pch transcoder B
[    6.574881] [drm:intel_pch_fifo_underrun_irq_handler [i915]] *ERROR* PCH transcoder B FIFO underrun

I get this same message, whether gdm is enabled or disabled.

If I do Ctrl+Alt+F2, then I get to login as user, and after that if I do <code>startx</code>, it tells me that the X server is already running. But at least I can do things without a GUI; which enabled me to get my log files. They are here:
https://drive.google.com/folderview?id= … sp=sharing

I searched for these error messages online, and found a multitude of different causes. I have no idea what to investigate now.
Any advice on what to investigate would be very much appreciated.

Last edited by mascip (2015-04-24 20:42:31)

mascip

Member

Registered: 2015-02-10

Posts: 29

Re: Problem with lightdm turned into problem with X server, maybe...

Sorry, I was wrong: after restarting one more time, now that gdm is disabled, I get to login, and then startx works.

So I can use the GUI again (yipee!), but not with a Login manager.

mascip

Member

Registered: 2015-02-10

Posts: 29

Re: Problem with lightdm turned into problem with X server, maybe...

Ok, after reading the Xorg.0.log and this post I installed acpid, enabled lightdm, and now lightdm starts again. It still won't let me login though. And I still get the 4 lines of "fifo underrun" error messages but they are not blocking anymore.

Then I went through

journalct -u lightdm

and got this error messages:

-- Reboot --
Mar 09 01:58:55 mascip-desk lightdm[296]: ** (lightdm:296): WARNING **: Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.Acco
Mar 09 01:58:55 mascip-desk lightdm[296]: ** (process:2379): WARNING **: Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.Acc
Mar 09 01:58:55 mascip-desk lightdm[2379]: pam_unix(lightdm-greeter:session): session opened for user lightdm by (uid=0)
Mar 09 01:59:52 mascip-desk lightdm[296]: ** (process:2779): WARNING **: Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.Acc
Mar 09 01:59:52 mascip-desk lightdm[2779]: pam_unix(lightdm:session): session opened for user user by (uid=0)
Mar 09 03:08:24 mascip-desk lightdm[296]: Failed to get D-Bus connection
Mar 09 03:08:24 mascip-desk systemd[1]: lightdm.service: main process exited, code=exited, status=1/FAILURE
Mar 09 03:08:24 mascip-desk systemd[1]: Unit lightdm.service entered failed state.
Mar 09 03:08:24 mascip-desk systemd[1]: lightdm.service failed.
-- Reboot --
Mar 09 03:08:48 mascip-desk lightdm[227]: ** (lightdm:227): WARNING **: Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.Acco.....

And after reading that post
I did

pacman -Suy

to refresh the system, but I get the same error message and it still doesn't work: when I type my password as a used in lightdm, it won't let me in. But I can enter my session as root.

When I disable lightdm, then I still see the 4 lines of "fifo underrun" but they are not blocking, and then after logging in I can do

startx

and the GUI starts properly.
What is the difference between trying to enter my session as user via lightdm, or without lightdm? One doesn't work and the other one does...

Last edited by mascip (2015-04-25 07:54:26)

anidel

Member

Registered: 2015-05-05

Posts: 2

Re: Problem with lightdm turned into problem with X server, maybe...

Hi,

just had the same issue...had to disable i915 Vertical Synchronization (VSYNC):

https://wiki.archlinux.org/index.php/Intel_graphics

by creating the .drirc in my home directory and entering:

<device screen="0" driver="dri2">
	<application name="Default">
		<option name="vblank_mode" value="0"/>
	</application>
</device>

Last edited by anidel (2015-05-05 18:02:43)

anidel

Member

Registered: 2015-05-05

Posts: 2

Re: Problem with lightdm turned into problem with X server, maybe...

Actually scratch that...it works by simply logging out and back again!