Created attachment 298045 [details]
photo of my notebook's internal display

Hi,

starting with 5.13.0 (RCs not tested) I can't use my notebook's internal display anymore. There is just graphical noise and some rainbow coloured vertical bars (I'll attach a photo for illustration). Brightness control works on that monitor, xrandr also for turning it off (and on). This "noise" occurs already in tty before X starts, but after I enter my LUKS passphrase as my initramfs requests.

It's not a hardware issue, as it occurs only and reproducible on linux-5.13, not on older kernels or e.g. EFI menus or the bootloader.

I run Gentoo/Linux with a hardened toolchain and tried gentoo-sources[1] aswell as the vanilla kernel directly from kernel.org (with identical outcome).

I've seen no difference in dmesg from 5.13 to pre-5.13 kernels, and I didn't change BIOS settings and didn't update the EFI.

My device is a Lenovo Thinkpad T14s with an "AMD Ryzen 7 PRO 4750U with Radeon Graphics".

I'll attache the mentioned photo aswell as my kernel config and my dmesg output from 5.13.5. Please tell me if I can provide you other helpful information.

Kind regards,
Nils