light dm ignores selected session type and always logs me into unity

[Andreas]

this started happening two days ago or so. Previously, I've selected "Gnome" or "Gnome Classic" @ the lightdm login (after selecting my username) and lightdm would log me into the selected session. However, whatever I select now, I always end up in unity.
---
ApportVersion: 1.23-0ubuntu2
Architecture: amd64
DistroRelease: Ubuntu 11.10
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
NonfreeKernelModules: nvidia wl
Package: lightdm 1.0.0-0ubuntu2
PackageArchitecture: amd64
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 3.0.0-12.19-generic 3.0.4
Tags: oneiric running-unity
Uname: Linux 3.0.0-12-generic x86_64
UpgradeStatus: Upgraded to oneiric on 2011-09-23 (5 days ago)
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare

[Andreas (andreas-kotowicz)]

I tried to attach more info to this bug (calling 'apport-collect 862127') but unfortunately I always get a message saying "No additional information collected".
Are there any files that I should upload manually?

[Andreas (andreas-kotowicz)]

apport information

[Robert Ancell (robert-ancell)]

Hi the appropriate log is /var/log/lightdm/ligthdm.log after you have logged in.

[Andreas (andreas-kotowicz)]

according to this log file, I requested the session 'Ubuntu' - but that's not correct. I always select 'Gnome'

[Andreas (andreas-kotowicz)]

I just noticed that this issue only occurs on a system that I've updated from 11.04 to 11.10. A clean install is not affected by this bug.

[Andreas (andreas-kotowicz)]

Once I remove unity completely, I can login back into gnome.

(I removed unity like this:

sudo apt-get remove unity unity-2d-places unity-2d unity-2d-panel unity-2d-spread unity-asset-pool unity-services unity-lens-files unity-lens-music unity-lens-applications gir1.2-unity-4.0 unity-common indicator-sound indicator-power indicator-appmenu libindicator6 indicator-application evolution-indicator indicator-datetime indicator-messages libnux-1.0-0

)

[ubertoo (ubertoo)]

I'm affected by this as well, upgrade from 11.04. Any lightdm session sends me into Unity, including failsafe xterm. If I switch login managers to gdm it works as expected.

sudo dpkg-reconfigure gdm

[Andreas (andreas-kotowicz)]

for those who are affected by this bug, here's a workaround:

$ cd /usr/share/gnome-session/sessions
$ sudo mv ubuntu.session ubuntu.session.dontuse
$ sudo mv gnome.session ubuntu.session

restart lightdm and now you will always drop into gnome-shell.

[kenjo (ken-kenjo)]

I have a me to on this one. The user that fail was upgraded from a 10.10 release to 11.10. Always end up in unity. a newly created account is able to select session.

Is there some way to debug this. Is there some shell script that I can put debug prinouts in.

What command do the lightdm actually run for the different sessions ?? I have no idea of where to look . Is this a fallback effect in that gnome 3 is started fail on something and we fall back to unity or is unity actually started from lightdm even when a different session was selected.

[kenjo (ken-kenjo)]

well this was interesting.

I found out that it starts /usr/sbin/lightdm-session that is a shell script so I added "set -x" as the first thing to be able to see where things was going wrong and then it actually worked.

[kenjo (ken-kenjo)]

Ok the last entry was not valid. something else was making it work.

I now started my computer again and have unity AGAIN.

Turns out that it is actually lightdm that provide the incorrect value in GDMSESSION environment variable.
here is a dump of the first part of /usr/sbin/lightdm-session.

+ echo Running X session wrapper
Running X session wrapper
+ [ -f /etc/profile ]
+ echo Loading profile from /etc/profile
Loading profile from /etc/profile
+ . /etc/profile
+ [ -d /etc/profile.d ]
+ [ -r /etc/profile.d/ati-fglrx.sh ]
+ . /etc/profile.d/ati-fglrx.sh
+ [ ]
+ LIBGL_DRIVERS_PATH=/usr/lib32/dri:/usr/lib64/dri
+ export LIBGL_DRIVERS_PATH
+ [ -r /etc/profile.d/bash_completion.sh ]
+ . /etc/profile.d/bash_completion.sh
+ [ -z -o -z $ -o -n ]
+ return
+ unset i
+ [ $ ]
+ [ ]
+ id -u
+ [ 1004 -eq 0 ]
+ PS1=$
+ [ -f /home/kenjo/.profile ]
+ [ -f /etc/xprofile ]
+ [ -f /home/kenjo/.xprofile ]
+ xresourcedir=/etc/X11/Xresources
+ [ -d /etc/X11/Xresources ]
+ echo Loading resource: /etc/X11/Xresources/x11-common
Loading resource: /etc/X11/Xresources/x11-common
+ xrdb -nocpp -merge /etc/X11/Xresources/x11-common
+ xresourcefile=/home/kenjo/.Xresources
+ [ -f /home/kenjo/.Xresources ]
+ [ -f /etc/X11/Xkbmap ]
+ [ -f /home/kenjo/.Xkbmap ]
+ [ -z ]
+ [ -f /etc/X11/Xmodmap ]
+ [ -f /home/kenjo/.Xmodmap ]
+ unset XKB_IN_USE
+ xinitdir=/etc/X11/xinit/xinitrc.d
+ [ -d /etc/X11/xinit/xinitrc.d ]
+ xsessionddir=/etc/X11/Xsession.d
+ OPTIONFILE=/etc/X11/Xsession.options
+ USERXSESSION=/home/kenjo/.xsession
+ USERXSESSIONRC=/home/kenjo/.xsessionrc
+ ALTUSERXSESSION=/home/kenjo/.Xsession
+ [ -d /etc/X11/Xsession.d ]
+ ls /etc/X11/Xsession.d
+ script=/etc/X11/Xsession.d/00_handle_guest_session
+ echo Loading X session script /etc/X11/Xsession.d/00_handle_guest_session
Loading X session script /etc/X11/Xsession.d/00_handle_guest_session
+ [ -r /etc/X11/Xsession.d/00_handle_guest_session -a -f /etc/X11/Xsession.d/00_handle_guest_session ]
+ expr 00_handle_guest_session : ^[[:alnum:]_-]\+$
+ . /etc/X11/Xsession.d/00_handle_guest_session
+ GDMSESSION=ubuntu
+ [ xubuntu = xguest-restricted ]
+ script=/etc/X11/Xsession.d/20x11-common_process-args

as can be seen GDMSESSION=ubuntu and it should have been gnome.

[qubix (jakkul)]

I confirm the same issue on my system 11.10 upgraded from 11.04.

[Matthew Ames (supermatt)]

Hi,

I can confirm that I am affected by this bug too.

My lightdm.conf says this:
[SeatDefaults]
user-session=gnome-shell
autologin-user=matthew
autologin-user-timeout=0
greeter-session=unity-greeter

But when I log in, /var/log/lightdm/lightdm.log states:

[+0.00s] DEBUG: Logging to /var/log/lightdm/lightdm.log
[+0.00s] DEBUG: Starting Light Display Manager 1.0.6, UID=0 PID=10997
[+0.00s] DEBUG: Loaded configuration from /etc/lightdm/lightdm.conf
[+0.00s] DEBUG: Using D-Bus name org.freedesktop.DisplayManager
[+0.00s] DEBUG: Registered seat module xlocal
[+0.00s] DEBUG: Registered seat module xremote
[+0.00s] DEBUG: Adding default seat
[+0.00s] DEBUG: Starting seat
[+0.00s] DEBUG: Starting new display for automatic login as user matthew
[+0.00s] DEBUG: Starting local X display
[+0.00s] DEBUG: Using VT 7
[+0.00s] DEBUG: Activating VT 7
[+0.00s] DEBUG: Logging to /var/log/lightdm/x-0.log
[+0.01s] DEBUG: Writing X server authority to /var/run/lightdm/root/:0
[+0.01s] DEBUG: Launching X Server
[+0.01s] DEBUG: Launching process 11001: /usr/bin/X :0 -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch
[+0.01s] DEBUG: Waiting for ready signal from X server :0
[+0.01s] DEBUG: Acquired bus name org.freedesktop.DisplayManager
[+0.01s] DEBUG: Registering seat with bus path /org/freedesktop/DisplayManager/Seat0
[+0.78s] DEBUG: Got signal 10 from process 11001
[+0.78s] DEBUG: Got signal from X server :0
[+0.78s] DEBUG: Connecting to XServer :0
[+0.78s] DEBUG: Automatically logging in user matthew
[+0.79s] DEBUG: pam_start("lightdm-autologin", "matthew") -> (0xb099a0, 0)
[+0.79s] DEBUG: pam_authenticate(0xb099a0, 0) -> 0 (Success)
[+0.79s] DEBUG: pam_acct_mgmt(0xb099a0, 0) -> 0 (Success)
[+0.79s] DEBUG: User matthew authorized
[+0.80s] DEBUG: Using session ubuntu
[+0.80s] DEBUG: Starting user session
[+0.81s] DEBUG: Dropping privileges to uid 1000
[+0.81s] DEBUG: Restoring privileges
[+0.81s] DEBUG: Dropping privileges to uid 1000
[+0.81s] DEBUG: Writing /home/matthew/.dmrc
[+0.85s] DEBUG: Restoring privileges
[+0.87s] DEBUG: Starting session ubuntu as user matthew
[+0.87s] DEBUG: Logging to /home/matthew/.xsession-errors
[+0.87s] DEBUG: Launching session
[+0.87s] DEBUG: pam_set_item(0xb099a0, 3, ":0") -> 0 (Success)
[+0.87s] DEBUG: pam_open_session(0xb099a0, 0) -> 0 (Success)
[+0.90s] DEBUG: Opened ConsoleKit session 3e924aabbe6a65f6b372503900000010-1330695884.447217-1893360978
[+0.90s] DEBUG: Dropping privileges to uid 1000
[+0.90s] DEBUG: Adding session authority to /home/matthew/.Xauthority
[+0.93s] DEBUG: Restoring privileges
[+0.93s] DEBUG: Launching process 11013: /usr/sbin/lightdm-session '/usr/bin/gnome-session --session=ubuntu'
[+0.94s] DEBUG: New display ready, switching to it
[+0.94s] DEBUG: Activating VT 7
[+0.94s] DEBUG: pam_setcred(0xb099a0, PAM_ESTABLISH_CRED) -> 0 (Success)
[+0.94s] DEBUG: PAM returns environment 'PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games LANG=en_GB.UTF-8 LANGUAGE=en_GB:en'
[+0.94s] DEBUG: Registering session with bus path /org/freedesktop/DisplayManager/Session0

As you can see, there is some confusion somewhere and it's getting the wrong session type from somewhere. I know ...

[johnathan schwartz (johnathanschwartz)]

This effects me, persistent live-usb session, not upgraded from 11.04, it's the standard ubuntu-11.10-desktop-i386.iso

[Benjamin (nailartcenter)]

Can the problem be dependent on graphics card driver? I mean, in terms of installed drivers, but can not be used because your video card is not installed..

[kenjo (ken-kenjo)]

On Mon, 2012-04-23 at 00:37 +0000, Benjamin wrote:
> Can the problem be dependent on graphics card driver? I mean, in terms
> of installed drivers, but can not be used because your video card is not
> installed..
>

No this is not it as I can use the session if I start it manually by
overriding the value light-dm uses. It probably is some configuration
value that is invalid or something so it gets the default value of
ubuntu as session.

It works if I create e new user and login with that.