After Stable Update 2021-09-24 LightDM no longer automatically start

[D.Dave]

I rebooted again for execute lightdm --test-mode --debug to get a debug log:

Summary

[+0.00s] DEBUG: Logging to /home/dave/.cache/lightdm/log/lightdm.log
[+0.00s] DEBUG: Starting Light Display Manager 1.30.0, UID=1000 PID=813
[+0.00s] DEBUG: Loading configuration dirs from /usr/share/lightdm/lightdm.conf.d
[+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: Running in user mode
[+0.00s] DEBUG: Registered seat module local
[+0.00s] DEBUG: Registered seat module xremote
[+0.00s] DEBUG: Using D-Bus name org.freedesktop.DisplayManager
[+0.05s] DEBUG: _g_io_module_get_default: Found default implementation gvfs (GDaemonVfs) for ‘gio-vfs’
[+0.05s] DEBUG: Monitoring logind for seats
[+0.05s] DEBUG: New seat added from logind: seat0
[+0.05s] DEBUG: Seat seat0: Loading properties from config section Seat:*
[+0.05s] DEBUG: Seat seat0 has property CanMultiSession=no
[+0.05s] DEBUG: Seat seat0: Starting
[+0.05s] DEBUG: Seat seat0: Creating greeter session
[+0.17s] DEBUG: Loading users from org.freedesktop.Accounts
[+0.17s] DEBUG: User /org/freedesktop/Accounts/User1000 added
[+0.18s] DEBUG: Seat seat0: Creating display server of type x
[+0.18s] DEBUG: Could not run plymouth --ping: Failed to execute child process “plymouth” (No such file or directory)
[+0.18s] DEBUG: Seat seat0: Starting local X display
[+0.18s] DEBUG: XServer 0: Logging to /home/dave/.cache/lightdm/log/x-0.log
[+0.18s] WARNING: XServer 0: Failed to make authority directory /run/lightdm/root: Permission denied
[+0.18s] DEBUG: XServer 0: Writing X server authority to /run/lightdm/root/:0
[+0.18s] WARNING: XServer 0: Failed to write authority: Failed to open X authority /run/lightdm/root/:0: No such file or directory
[+0.18s] DEBUG: XServer 0: Launching X Server
[+0.18s] DEBUG: Launching process 847: /usr/bin/X :0 -seat seat0 -auth /run/lightdm/root/:0 -nolisten tcp
[+0.18s] DEBUG: XServer 0: Waiting for ready signal from X server :0
[+0.18s] DEBUG: Acquired bus name org.freedesktop.DisplayManager
[+0.18s] DEBUG: Registering seat with bus path /org/freedesktop/DisplayManager/Seat0
[+0.18s] WARNING: Could not enumerate user data directory /var/lib/lightdm-data: Error opening directory '/var/lib/lightdm-data': Permission denied
[+0.18s] DEBUG: Process 847 exited with return value 1
[+0.18s] DEBUG: XServer 0: X server stopped
[+0.18s] DEBUG: XServer 0: Removing X server authority /run/lightdm/root/:0
[+0.18s] DEBUG: Seat seat0: Display server stopped
[+0.18s] DEBUG: Seat seat0: Stopping session
[+0.18s] DEBUG: Seat seat0: Session stopped
[+0.18s] DEBUG: Seat seat0: Stopping display server, no sessions require it
[+0.18s] DEBUG: Seat seat0: Stopping; greeter display server failed to start
[+0.18s] DEBUG: Seat seat0: Stopping
[+0.18s] DEBUG: Seat seat0: Stopped
[+0.18s] DEBUG: Required seat has stopped
[+0.18s] DEBUG: Stopping display manager
[+0.19s] DEBUG: Display manager stopped
[+0.19s] DEBUG: Stopping daemon
[+0.19s] DEBUG: Exiting with return value 1

[megavolt]

@D.Dave

[+0.18s] WARNING: Could not enumerate user data directory /var/lib/lightdm-data: Error opening directory '/var/lib/lightdm-data': Permission denied

Can you provide your configs?

/etc/lightdm/lightdm.conf
/etc/lightdm/lightdm-gtk-greeter.conf
/etc/lightdm/lightdm-webkit2-greeter.conf

[banjo]

Around 6 months ago I faced instabilities with lightdm-gtk-greeter (doubled login-gui, unthemed, top left on my screen sometimes) .
Since replacing lightdm-gtk-greeter and it’s settings with slick-greeter and lightdm-settings my system runs fine. Worth a try.
And no, I don’t use pikom.

[D.Dave]

@megavolt

Can you provide your configs?

/etc/lightdm/lightdm.conf
/etc/lightdm/lightdm-gtk-greeter.conf
/etc/lightdm/lightdm-webkit2-greeter.conf

lightdm.conf:

[LightDM]
logind-check-graphical=true
run-directory=/run/lightdm
[Seat:*]
[Seat:*]
greeter-session = lightdm-webkit2-greeter
user-session=xfce
session-wrapper=/etc/lightdm/Xsession
[XDMCPServer]
[VNCServer]

lightdm-gtk-greeter.conf (is not used: I use lightdm-webkit2-greeter; I tried to switch back to lightdm-gtk-greeter but the result is the same)

[greeter]

/etc/lightdm/lightdm-webkit2-greeter.conf:

[greeter]
debug_mode          = false
detect_theme_errors = true
screensaver_timeout = 300
secure_mode         = true
time_format         = LT
time_language       = auto
webkit_theme = sequoia

---

[+0.18s] WARNING: Could not enumerate user data directory /var/lib/lightdm-data: Error opening directory '/var/lib/lightdm-data': Permission denied

So there is a permission issue… But such directory is owned by lightdm:

[D.Dave]

@banjo

I faced instabilities with lightdm-gtk-greeter

I don’t use lightdm-gtk-greeter, but lightdm-webkit2-greeter, which has always worked fine; the strange thing is that since two days ago it worked without issues; the problem start to appear since the stable update from yesterday (which didn’t provided updates for lightdm); I also restored a system backup with timeshift, but the described issue is still there.

[banjo]

@D.Dave

greeter-session = lightdm-webkit2-greeter

change to:
greeter-session=lightdm-webkit2-greeter

[D.Dave]

Done: doesn’t help.

[megavolt]

It is really weird… at this point I have no idea. I come back to you if I have another idea. Maybe someone know what your actual problem is…

I have no system which is running lightdm or xfce4 right now.

[D.Dave]

In the meantime I thank you for your efforts, for devoting your time

[maycne.sonahoz]

This might be relevant:

System stuck at Light Display Manager start

Hi, I recently did a kernel update to 5.9.11-3 and when trying to start that particular instance it stucks loading at the lightmanager load. The lightmanager log output: [+0.00s] DEBUG: Logging to /home/ray/.cache/lightdm/log/lightdm.log [+0.00s] DEBUG: Starting Light Display Manager 1.30.0, UID=1000 PID=1685 [+0.00s] DEBUG: Loading configuration dirs from /usr/share/lightdm/lightdm.conf.d [+0.00s] DEBUG: Loading configuration dirs from /usr/local/share/lightdm/lightdm.conf.d [+0.00s] DEBUG: L…

[D.Dave]

I don’t have hybrid graphic (Intel/Nvidia): I have only Intel; I also tried to boot with different kernels, without success.

[D.Dave]

I’m going to accept the fact of login using TTY instead of graphic greeter.

I also tried to uninstall again lightdm and lightdm-greeter and delete his directories (I discovered that are reported in /usr/lib/tmpfiles.d/lightdm.conf)

/var/lib/lightdm
/var/lib/lightdm-data
/run/lightdm
/var/cache/lightdm

Then reboot for the umpteenth time, reinstall it again and so on: lightdm doesn’t want to autostart anymore, and I repeat: I also restored the system backup from the day before the stable update.
I also disabled the service lightdm.service: is useless, since it doesn’t autostart anymore: is a weight on the startup.

So I login from TTY, by executing startxfce4, and I had to replicate the environment variables from ~/.profile to ~/.bashrc (eg, like export QT_QPA_PLATFORMTHEME="qt5ct");
This because seems that by starting the graphical environment from startxfce4 doesn’t source ~/.profile: I verified this by doing echo $QT_QPA_PLATFORMTHEME: resulted in an emtpy output, is ok instead by having the env variables in ~/.bashrc.

still in ~/.bashrc, I made an alias to quickly execute startxfce4:
alias sd="startxfce4" (sd stands for Start Desktop).

lxdm, the alternative for lightdm, works fine, but is not customizable like lightdm, and furthermore, the system’s mouse theme is not applyed by lxdm.

[pheiduck]

Hm, shouldn’t be a thing depending on your hardware. Maybe try a newer LTS Kernel 5.4 or 5.10

$ sudo mhwd-kernel -i linux54
$ sudo mhwd-kernel -i linux510

I have no issues with this on my old Lenovo ThinkPad 60.

[D.Dave]

I already tried newer kernels, without success.

[pheiduck]

Other solutions are:

Lightdm failed to start with Kernel 5.11.14

Put amdgpu to your modules in mkinitcpio … https://wiki.archlinux.org/index.php/Kernel_mode_setting#Early_KMS_start

[Stable Update] 2021-08-27 - Kernels, Cutefish, NetworkManager, Gnome, Pamac, Mesa, Browsers, Xorg-Server, LibreOffice

I also had the problem that LightDM failed during startup. For me adding logind-check-graphical=true to the [LightDM] section in /etc/lightdm/lightdm.conf did the trick.

[D.Dave]

I already had, since months, i915 in mkinitcpio, as well I also tried logind-check-graphical=true in /etc/lightdm/lightdm.conf.

[Fabby]

As you seem to be the only one having this issue, moved that conversation into the original topic until we have a solution / workaround after which we can update the wiki…

[snowdust]

I am also experiencing the same issue. My CPU is Ryzen 3 3200G, mobo Asus TUF Gaming x570-Plus, running kernel 5.14.10-1, and Cinnamon 5.0.5 DE. I opened the file mkinitcpio as root and there is no MODULES section, see content:

# mkinitcpio preset file for the 'linux514' package

ALL_config="/etc/mkinitcpio.conf"
ALL_kver="/boot/vmlinuz-5.14-x86_64"

PRESETS=('default' 'fallback')

#default_config="/etc/mkinitcpio.conf"
default_image="/boot/initramfs-5.14-x86_64.img"
#default_options=""

#fallback_config="/etc/mkinitcpio.conf"
fallback_image="/boot/initramfs-5.14-x86_64-fallback.img"
fallback_options="-S autodetect"

Editing the /etc/lightdm/lightdm.conf by replacing false by true did not work.
I can only access the desktop by launching “startx” in tty.
Thanks for any help.

[Fabby]

@snowdust

I opened the file mkinitcpio as root and there is no MODULES section, see content:

You’re supposed to add it, but that looks like the wrong file. What’s it’s full pathname?

[snowdust]

Full path name: /etc/mkinitcpio.d/linux514.preset
Hope this helps.