Arch Linux

Krygen

Banned

Registered: 2021-09-10

Posts: 39

Kernel Error: systemd-backlight@backlight:acpi_video0.service

I am having issue with that service. I am disabling it, however it keeps enables itself at the boot sequence.

× systemd-backlight@backlight:acpi_video0.service - Load/Save Screen Backlight Brightness of backlight:acpi_video0
     Loaded: loaded (/usr/lib/systemd/system/systemd-backlight@.service; static)
     Active: failed (Result: exit-code) since Sat 2021-09-25 10:25:34 +03; 32min ago
       Docs: man:systemd-backlight@.service(8)
    Process: 500 ExecStart=/usr/lib/systemd/systemd-backlight load backlight:acpi_video0 (code=exited, status=1/FAILURE)
   Main PID: 500 (code=exited, status=1/FAILURE)
        CPU: 3ms

Sep 25 10:25:34 thinkpad systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:acpi_video0...
Sep 25 10:25:34 thinkpad systemd-backlight[500]: Failed to get backlight or LED device 'backlight:acpi_video0': No such device
Sep 25 10:25:34 thinkpad systemd[1]: systemd-backlight@backlight:acpi_video0.service: Main process exited, code=exited, status=1/FAILURE
Sep 25 10:25:34 thinkpad systemd[1]: systemd-backlight@backlight:acpi_video0.service: Failed with result 'exit-code'.
Sep 25 10:25:34 thinkpad systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight:acpi_video0.

There are two services working as backlight services for me, the second one working properly.

● systemd-backlight@backlight:amdgpu_bl0.service - Load/Save Screen Backlight Brightness of backlight:amdgpu_bl0
     Loaded: loaded (/usr/lib/systemd/system/systemd-backlight@.service; static)
     Active: active (exited) since Sat 2021-09-25 10:25:34 +03; 34min ago
       Docs: man:systemd-backlight@.service(8)
    Process: 501 ExecStart=/usr/lib/systemd/systemd-backlight load backlight:amdgpu_bl0 (code=exited, status=0/SUCCESS)
   Main PID: 501 (code=exited, status=0/SUCCESS)
        CPU: 4ms
i
Sep 25 10:25:34 thinkpad systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:amdgpu_bl0...
Sep 25 10:25:34 thinkpad systemd[1]: Finished Load/Save Screen Backlight Brightness of backlight:amdgpu_bl0.

How can I disable the first service or fix, whilst it is not working, I am not having any issue with my backlight at all. So I am even good to go with deleting that service file, but I could not find it anywhere in /usr/lib/systemd/system.

OS: Arch Linux x86_64
Host: 20T60024TX ThinkPad E14 Gen 2
Kernel: 5.14.7

Last edited by Krygen (2021-09-25 08:04:10)

snakeroot

Member

Registered: 2012-10-06

Posts: 164

Re: Kernel Error: systemd-backlight@backlight:acpi_video0.service

You need to mask that service not just disable it (cf. Wiki entry on Thinkpad T14 (AMD) Gen 1).

sudo systemctl mask systemd-backlight@backlight:acpi_video0.service

For background, see Fedora Magazine article on masking units.