[Solved] Installing SDDM + Plasma results in black screen

salnet · 2025-09-07 21:18:13

Hello folks,

I'm using Arch Linux for almost 5 years now on my old notebook. My DE is Plasma and I'm using X11 due to compatibility issues with some of my applications. Everything works great, expect for the notebook being old (8th gen Intel CPU).
So I recently bought a new notebook (Lenovo ThinkPad E14 Gen 6) and installed Arch with the latest ISO (9/2025).
Here began the mystery. On my external screen the last 3.5-4 lines of the shell were not showing (on the laptop screen all was well, the old laptop never had this issue). Ignored, as I'm not often working in a TTY.

Installation was fine, after booting to SDDM there only showed up a black screen with no cursor. I installed the same packages as before on my old laptop (replacing xf86-video-intel with mesa):
xorg-server xorg-xinit xorg-drivers mesa xf86-input-synaptics xorg-twm vulkan-intel vulkan-icd-loader linux-firmware intel-media-driver sof-tools sof-firmware plasma plasma-wayland-protocols egl-wayland sddm konsole dolphin kate plasma-x11-session kwin-x11

After figuring our a bit, it seems that I need a sddm.conf. I created one and sddm was able to start. On my old laptop I don't had weither a /etc/sddm.conf nor /etc/sddm.d/*.conf.
The files in /usr/lib/sddm/ were both the same on my old and my new laptop-

The /etc/sddm.conf I created:

[General]
DisplayServer=wayland
GreeterEnvironment=QT_WAYLAND_SHELL_INTEGRATION=layer-shell
InputMethod=qtvirtualkeyboard
Namespaces=
Numlock=on

[Theme]
CursorSize=
CursorTheme=breeze
DisableAvatarsThreshold=7
EnableAvatars=true
FacesDir=/usr/share/sddm/faces
Font=
ThemeDir=/usr/share/sddm/themes

[Users]
DefaultPath=/usr/local/bin:/usr/bin:/bin
HideShells=
HideUsers=
RememberLastSession=true
RememberLastUser=true
ReuseSession=true

[Wayland]
CompositorCommand=kwin_wayland --drm --no-global-shortcuts --no-lockscreen --inputmethod maliit-keyboard --locale1
EnableHiDPI=true
SessionCommand=/usr/share/sddm/scripts/wayland-session
SessionDir=/usr/local/share/wayland-sessions,/usr/share/wayland-sessions
SessionLogFile=.local/share/sddm/wayland-session.log

[X11]
DisplayCommand=/usr/share/sddm/scripts/Xsetup
DisplayStopCommand=/usr/share/sddm/scripts/Xstop
EnableHiDPI=true
ServerArguments=-nolisten tcp
ServerPath=/usr/bin/X
SessionCommand=/usr/share/sddm/scripts/Xsession
SessionDir=/usr/local/share/xsessions,/usr/share/xsessions
SessionLogFile=.local/share/sddm/xorg-session.log
XephyrPath=/usr/bin/Xephyr

With this changes sddm started and I had the ability to login to a wayland plasma session. When trying to login to a X11 plasma sessin, the screen got black again. I'm not sure what to do to start X11, I didn't need such a file before.

Versions are same on kernel (6.16.5-arch1-1) and plasma (6.4.4).

Is there a way someone can help me?

Kind regards
salnet

Last edited by salnet (2025-09-10 15:27:05)

seth · 2025-09-08 08:11:04

Please post your Xorg log, https://wiki.archlinux.org/title/Xorg#General

salnet · 2025-09-08 18:31:10

Here is my ~/.local/share/xorg/Xorg.0.log

[tamara@thinkpad]$ lspci | grep VGA
00:02.0 VGA compatible controller: Intel Corporation Meteor Lake-P [Intel Arc Graphics] (rev 08)

Last edited by salnet (2025-09-08 18:55:20)

seth · 2025-09-08 20:08:23

Remove xf86-video-intel and

grep -ri intel /{etc,usr/share}/X11/xorg.conf*

every config that references it (look like optimus-manager?)

jotix · 2025-09-08 22:04:09

Hi, after some update sddm stop to work and simply turn the monitor off after login.
I do some journalctl and wiki search with no much success.

In the troubleshooting phase I change the default shell from fish to bash, and that was the solution.
I needed to do work quickly, so stop wandering the reasons of what this was the case, so throw this here maybe there is a correlation

Last edited by jotix (2025-09-08 22:07:39)

salnet · 2025-09-09 04:25:23

seth wrote:

Remove xf86-video-intel

Thank you,
I did not install xf86-video-intel manually; it must have come via a metapackage. It is now uninstalled.

After rebooting, when I log in to the X11 session, I am immediately thrown back to the SDDM login screen.
Here is the new log.

seth wrote:

grep -ri intel /{etc,usr/share}/X11/xorg.conf*
every config that references it)

Did not produce any results.

seth wrote:

(look like optimus-manager?)

By Optimus, do you mean something like bbswitch or bumblebee?
I don't have those installed—I don't have a dedicated graphics card either, just the IGP.

jotix wrote:

In the troubleshooting phase I change the default shell from fish to bash, and that was the solution.

bash is my default-shell.

seth · 2025-09-09 06:57:35

    grep -ri intel /{etc,usr/share}/X11/xorg.conf*
Did not produce any results.

You may want to check that again:

[    33.613] (**) |   |-->Device "Intel Graphics"
…
[    33.619] (II) LoadModule: "intel"
[    33.619] (WW) Warning, couldn't open module intel
[    33.619] (EE) Failed to load module "intel" (module does not exist, 0)
[    33.619] (EE) No drivers available.
[    33.619] (EE) 
Fatal server error:
[    33.619] (EE) no screens found(EE) 
[    33.619] (EE)

Sth. like this: https://aur.archlinux.org/packages/optimus-manager-git
Something™ writes that xorg config entry, in doubt dynamically, might be OM, asusd, supergfxctl, stuff like that - but it needs to go away.

salnet · 2025-09-10 10:30:41

I have now reset the device and started from scratch. There were too many bug fixes to solve the problem.
Instead of the xorg meta package, I have now explicitly deselected xf86-video-intel.
Nevertheless, I had to create /etc/sddm.conf with the above content. Login with X11 now works.

Thank you very much for your help in solving the problem.

seth · 2025-09-10 13:15:46

Please always remember to mark resolved threads by editing your initial posts subject - so others will know that there's no task left, but maybe a solution to find.
Thanks.

salnet · 2025-09-10 15:28:21

Thanks for the reminder. I just edited the initial post.

Arch Linux

#1 2025-09-07 21:18:13

[Solved] Installing SDDM + Plasma results in black screen

#2 2025-09-08 08:11:04

Re: [Solved] Installing SDDM + Plasma results in black screen

#3 2025-09-08 18:31:10

Re: [Solved] Installing SDDM + Plasma results in black screen

#4 2025-09-08 20:08:23

Re: [Solved] Installing SDDM + Plasma results in black screen

#5 2025-09-08 22:04:09

Re: [Solved] Installing SDDM + Plasma results in black screen

#6 2025-09-09 04:25:23

Re: [Solved] Installing SDDM + Plasma results in black screen

#7 2025-09-09 06:57:35

Re: [Solved] Installing SDDM + Plasma results in black screen

#8 2025-09-10 10:30:41

Re: [Solved] Installing SDDM + Plasma results in black screen

#9 2025-09-10 13:15:46

Re: [Solved] Installing SDDM + Plasma results in black screen

#10 2025-09-10 15:28:21

Re: [Solved] Installing SDDM + Plasma results in black screen

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