Lact causes the screen to flicker when it's running when I choose anything above 120Hz !

[DonCappuccin0]

Checklist

• The problem is not listed in the hardware support matrix as a known limitation
• I've included a debug snapshot if the issue is related to hardware configuration

Bug description

When I choose a refresh above 120Hz the screen start to show glitches and flickers.
https://github.com/user-attachments/assets/ab260e25-da05-4859-90b6-2a58e678e9fb

Reproduction

Simplified, easy to follow steps to reproduce the bug:

1.Run LACT
2.Choose a refresh above 120Hz

Actual result:

Screen shows glitches.

Expected result:

Run 165Hz without glitches.

Additional information

In order to avoid the glitch you shouldn't open LACT whatsoever, once you run it, even after closing the issue still persists.
LACT-sysfs-snapshot-20240730-200320.tar.gz

System info

CoreCtrl version: 1.4.1-2

Distribution: CachyOS

Kernel version: Linux 6.10.2-2-cachyos

GPU model: AMD RX 580 8GB

GPU driver: 

❯ glxinfo | grep Mesa
client glx vendor string: Mesa Project and SGI
OpenGL core profile version string: 4.6 (Core Profile) Mesa 24.1.4-arch1.3
OpenGL version string: 4.6 (Compatibility Profile) Mesa 24.1.4-arch1.3
OpenGL ES profile version string: OpenGL ES 3.2 Mesa 24.1.4-arch1.3
❯ glxinfo | grep -e OpenGL.vendor -e OpenGL.renderer
OpenGL vendor string: AMD
OpenGL renderer string: AMD Radeon RX 580 Series (radeonsi, polaris10, LLVM 18.1.8, DRM 3.57, 6.10.2-2-cachyos)

GPU driver parameters: amdgpu.ppfeaturemask=0xffffffff

[ahydronous]

It’s possible setting your featuremask value to 0xfffd7fff fixes the flicker, in which case this is a driver problem and not a LACT problem.

[ilya-zlobintsev]

It’s possible setting your featuremask value to 0xfffd7fff fixes the flicker, in which case this is a driver problem and not a LACT problem.

This might be true - you should try removing the ppfeaturemask option and enabling OC support via LACT instead. It will set the parameter to enable only the features needed for overdrive, and not everything like with 0xffffffff.

[Mershl]

you should try removing the ppfeaturemask option and enabling OC support via LACT instead. It will set the parameter to enable only the features needed for overdrive, and not everything like with 0xffffffff

just learned about this. unfortunately this fails on atomic desktop as initramfs generation is a bit more complicated there. would it be possible to include the target value of ppfeaturemask in the error mask, or show it in the "Overclocking information" bubble (for example if /boot/efi is not writeable) to grab and set it manually?

EDIT: thinking about it... it might even make sense to hint to users that the current mask doesn't fit the recommendation.

on Fedora Silverblue 40 it will create /etc/modprobe.d/99-amdgpu-overdrive.conf but fail when trying to regenerate initramfs (small bug: the dialog still reports Success at the top):

[shanefagan]

This isn't an LACT issue it is a Linux DRM issue for AMD https://gitlab.freedesktop.org/drm/amd/-/issues/3449