Failed to load/start module acpi_backlight errors in manjaro

I was using manjaro with kernel 5.7.15 for a while now. I remember when I updated it from 5.6 to 5.7 kernel, I started getting this acpi_backlight error but after 2-3 seconds, system would boot into gnome anyway. Today I had to re-install the OS for some reason, the only problem is now the system does not go into gnome.

I have tried disabling backlight service (systemd-backlight@.service) but that does not work. The system rarely boots into gnome (around 1 in 10 PC restarts) which is very annoying.
Since I have updated to the newer kernel anyway and previous fixes arent running, can anyone suggest me any new fix ?

I am running ryzen 2500u processor. The issue was not there with the previous installation with the same kernel

see theses topics
https://forum.manjaro.org/search?q=acpi_backlight

I have tried everything in there. Most people say that they have the same issue but their system boots into gnome so they ignore it. But my system does not go in the GUI. (not atleast 9 on 10 times) , it magically boots into GUI rarely.

● 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; vendor preset: disabled)
     Active: failed (Result: exit-code) since Tue 2020-08-25 19:56:38 IST; 48min ago
       Docs: man:systemd-backlight@.service(8)
    Process: 790 ExecStart=/usr/lib/systemd/systemd-backlight load backlight:acpi_video0 (code=exited, status=1/FAILURE)
   Main PID: 790 (code=exited, status=1/FAILURE)

Aug 25 19:56:38 luckygr8-nitroan51542 systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:acpi_video0...
Aug 25 19:56:38 luckygr8-nitroan51542 systemd-backlight[790]: Failed to get backlight or LED device 'backlight:acpi_video0': No such device
Aug 25 19:56:38 luckygr8-nitroan51542 systemd[1]: systemd-backlight@backlight:acpi_video0.service: Main process exited, code=exited, status=1/FAILURE
Aug 25 19:56:38 luckygr8-nitroan51542 systemd[1]: systemd-backlight@backlight:acpi_video0.service: Failed with result 'exit-code'.
Aug 25 19:56:38 luckygr8-nitroan51542 systemd[1]: Failed to start Load/Save Screen Backlight Brightness of backlight:acpi_video0.
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Such as?

Did you try adding acpi_backlight=vendor as a GRUB kernel parameter like mentioned in this post?

Yes I did. The next time there was just a black screen, not even the errors. I thought the OS had died. I switched to manjaro KDE and that distro also gives the acpi backlight issue but it boots straight into GUI seconds later. Why this happens is beyond me. I will stay with KDE for now untill the GNOME bugs get fixed !!

thanks for your reply and time

2 posts were split to a new topic: Boot fails with a blank screen

2 posts were merged into an existing topic: Boot fails with a blank screen due to acpi_backlight errors