Unable to change brightness

Desktop Environments Gnome
1

systemd-backlight@backlight:nvidia_0.service failed to activate.

I am unable to change the screen brightness through the sider and the keyboard shortcut. The brightness is set to the highest value and it’s very inconvenient.

~/ systemctl status systemd-backlight@backlight:nvidia_0.service
× systemd-backlight@backlight:nvidia_0.service - Load/Save Screen Backlight Brightness of backlight:nvidia_0
     Loaded: loaded (/usr/lib/systemd/system/systemd-backlight@.service; static)
     Active: failed (Result: exit-code) since Sat 2023-11-04 19:11:43 IST; 1min 4s ago
       Docs: man:systemd-backlight@.service(8)
    Process: 2339 ExecStart=/usr/lib/systemd/systemd-backlight load backlight:nvidia_0 (code=exited, status=1/FAILURE)
   Main PID: 2339 (code=exited, status=1/FAILURE)
        CPU: 30ms

Nov 04 19:11:45 endeavouros systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight:nvidia_0.
Nov 04 19:11:45 endeavouros systemd[1]: systemd-backlight@backlight:nvidia_0.service: Start request repeated too quickly.
Nov 04 19:11:45 endeavouros systemd[1]: systemd-backlight@backlight:nvidia_0.service: Failed with result 'exit-code'.
Nov 04 19:11:46 endeavouros systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight:nvidia_0.
Nov 04 19:11:46 endeavouros systemd[1]: systemd-backlight@backlight:nvidia_0.service: Start request repeated too quickly.
Nov 04 19:11:46 endeavouros systemd[1]: systemd-backlight@backlight:nvidia_0.service: Failed with result 'exit-code'.
Nov 04 19:11:46 endeavouros systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight:nvidia_0.
Nov 04 19:11:46 endeavouros systemd[1]: systemd-backlight@backlight:nvidia_0.service: Start request repeated too quickly.
Nov 04 19:11:46 endeavouros systemd[1]: systemd-backlight@backlight:nvidia_0.service: Failed with result 'exit-code'.
Nov 04 19:11:46 endeavouros systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight:nvidia_0.

~/ journalctl -b _PID=2339
Nov 04 19:11:43 endeavouros systemd-backlight[2339]: nvidia_0: Failed to write system 'brightness' attribute: Invalid argument

~/ journalctl -b --no-hostname -u systemd-backlight@backlight:acpi_video0.service -u systemd-udevd.service
Nov 04 19:09:23 systemd[1]: Starting Rule-based Manager for Device Events and Files...
Nov 04 19:09:23 systemd-udevd[232]: Using default interface naming scheme 'v253'.
Nov 04 19:09:23 systemd[1]: Started Rule-based Manager for Device Events and Files.
Nov 04 19:09:24 systemd[1]: Stopping Rule-based Manager for Device Events and Files...
Nov 04 19:09:25 systemd[1]: systemd-udevd.service: Deactivated successfully.
Nov 04 19:09:25 systemd[1]: Stopped Rule-based Manager for Device Events and Files.
Nov 04 19:09:25 systemd[1]: systemd-udevd.service: Consumed 1.775s CPU time.
Nov 04 19:09:26 systemd[1]: Starting Rule-based Manager for Device Events and Files...
Nov 04 19:09:26 systemd-udevd[402]: Using default interface naming scheme 'v253'.
Nov 04 19:09:26 systemd[1]: Started Rule-based Manager for Device Events and Files.
Nov 04 19:09:26 (udev-worker)[412]: nvidia_modeset: Process '/usr/bin/bash -c '/usr/bin/mknod -Z -m 666 /dev/nvidia-modeset c $(grep nvidia-frontend /proc/devices | cut -d \  -f 1) 254'' fail>
Nov 04 19:09:26 mtp-probe[453]: checking bus 1, device 3: "/sys/devices/pci0000:00/0000:00:14.0/usb1/1-9"
Nov 04 19:09:26 mtp-probe[453]: bus: 1, device: 3 was not an MTP device
Nov 04 19:09:26 (udev-worker)[423]: nvidia: Process '/usr/bin/bash -c '/usr/bin/mknod -Z -m 666 /dev/nvidiactl c $(grep nvidia-frontend /proc/devices | cut -d \  -f 1) 255'' failed with exit >
Nov 04 19:09:26 (udev-worker)[415]: nvidia: Process '/usr/bin/bash -c '/usr/bin/mknod -Z -m 666 /dev/nvidiactl c $(grep nvidia-frontend /proc/devices | cut -d \  -f 1) 255'' failed with exit >
Nov 04 19:09:26 (udev-worker)[415]: nvidia: Process '/usr/bin/bash -c 'for i in $(cat /proc/driver/nvidia/gpus/*/information | grep Minor | cut -d \  -f 4); do /usr/bin/mknod -Z -m 666 /dev/n>
Nov 04 19:09:26 (udev-worker)[423]: nvidia: Process '/usr/bin/bash -c 'for i in $(cat /proc/driver/nvidia/gpus/*/information | grep Minor | cut -d \  -f 4); do /usr/bin/mknod -Z -m 666 /dev/n>
Nov 04 19:09:27 mtp-probe[496]: checking bus 1, device 2: "/sys/devices/pci0000:00/0000:00:14.0/usb1/1-6"
Nov 04 19:09:27 mtp-probe[496]: bus: 1, device: 2 was not an MTP device
2

Same here, not found a solution:

3

Rolled back to 535.113.01 and will stick with that for the foreseeable future.

What frustrates me the most is that the brightness control won’t work for the longest time, then it will be fixed – just before the new “stable” release is pushed. The stable release re-breaks the brightness control and I’m back on the hamster wheel again.

I gave this a couple hours of troubleshooting yesterday before giving up and rolling back. My best guess is that NVIDIA’s install is not playing well with dracut and systemd. I tried forcing modules with:

/etc/dracut.conf.d/myflags.conf

# ...
force_drivers+=" nvidia nvidia_modeset nvidia_uvm nvidia_drm "
# ...

but no joy. The only thing I found that worked was

xrandr --output DP-2 --brightness 0.7

which isn’t something I want to script out for daily use. I have a working solution in the previous version and I’ll stick to that for now. Someday I’ll upgrade the drivers again.

Tech info with rollback driver:

[user@machinename ~]$ inxi -G
Graphics:
  Device-1: NVIDIA TU106M [GeForce RTX 2060 Mobile] driver: nvidia
    v: 535.113.01
  Device-2: Lite-On Integrated Camera driver: uvcvideo type: USB
  Display: x11 server: X.Org v: 21.1.9 driver: X: loaded: nvidia
    unloaded: modesetting gpu: nvidia,nvidia-nvswitch
    resolution: 1920x1080~144Hz
  API: EGL v: 1.5 drivers: nvidia platforms: gbm
  API: OpenGL v: 4.6.0 vendor: nvidia v: 535.113.01 renderer: NVIDIA
    GeForce RTX 2060/PCIe/SSE2
2 Likes
4
5

Looks like there is a fix in the works, at least for Legion 5 et al. I’m not knowledgeable enough to apply the patch, so I’ll wait for the next driver release.

NVIDIA forum post about the issue

Patch that fixes NVIDIA open and proprietary drivers

6

FIXED in 545.29.06.

2 Likes