Critical behaviour after suspension

[Samuele]

It has been a week or so that my laptop some times displays a strange error. Sometimes, after waking it from suspension, the screen powers on and the lock screen appears, but then the brightness of the screen starts raising on itself until it reaches maximum, at that point it seems to loop back to the minimum brightness and keeps rising to the maximum, but on every loop it raises faster; after a three or four loops the screen just shuts of completely, but the laptop is still on.
After some minutes, I think after the default suspension time, the screen seems to flicker and at that point I know I can wake it again (before this it just stays shut), but the issue happens again. This means that my only way to stop this from happening is powering off the laptop with the power button. I tried to unlock the environment by typing my password, but it seems nothing is working.
While the birghtness is doing this strange game I can unlock the environment by quickly typing my password and I can move around until the screen shuts off completely, which could be 4 seconds or so.

I do not know how to troubleshoot this, so if anyone could give me an hint on any command to display some logs about this I could manage to save them before the screen shuts off, the next time this happens.

Operating System: Fedora Linux 41
KDE Plasma Version: 6.2.4
KDE Frameworks Version: 6.9.0
Qt Version: 6.8.1
Kernel Version: 6.12.6-200.fc41.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 5700U with Radeon Graphics
Memory: 13.5 GiB of RAM
Graphics Processor: AMD Radeon Graphics
Manufacturer: LENOVO
Product Name: 21A4
System Version: ThinkBook 15 G3 ACL

[skyfishgoo]

maybe this can help

Brightness on startup

my 2nd monitor kept deviating from those settings by going dim like it was about to go to sleep and only after i open the widget and joggle the slider would it go back to the proper setting (my primary monitor didn’t even have a slider). the whole feature seems doughy and incomplete, so just disabled it. be sure to set the brightness levels first because after this change the sliders will be gone… or add the package for a separate gui control from my notes # to keep brightness levels from ch…

[Samuele]

Thank you, but I don’t really know if this is related, as my problem is not with startup but with waking up.
This other thread might be more related: Plasma 6.2: Black screen on wakeup
I even commented there, and I hope the fix they are talking about will solve my problem too.

[Samuele]

The issue has appeared even when disconnecting the laptop from the charger, so it seems to be an issue with power management.

[johnandmegh]

Hi - I don’t have an AMD GPU myself, but it sounds like you might be experiencing the issue from this bug report: 497823 – The brightness goes to max after waking the laptop from sleep.

Which is ultimately caused by a bug in the amdgpu driver, upstream in the Linux kernel: adaptive backlight management broken on vega since 6.12.5 (#3853) · Issues · drm / amd · GitLab

[Samuele]

Thank you very much, they in fact describe my issue. I suppose I can just wait for this to be solved in the kernel, maybe giving my experience in the reports.