Hello!

I run a AMD laptop "81NC Lenovo IdeaPad S340-15API" - AMD Ryzen 5 3500U 
with Radeon Vega 8 Graphics.
Recently some breakages started happening for me. In about 1h after 
boot-up while using a KDE desktop machine GUI would freeze. Sometimes it 
would be possible to move the mouse but the rest will be frozen. Screen 
may start blinking or go black.

I'm not sure if this is my kernel, firmware or the hardware.
I don't understands dmesg that's why I'm guessing, but I think it is the 
firmware since this behavior started around 2021-05-15.
 From my Portage logs I see that I updated my firmware on 2021-05-14 at 
18:16:06.
So breakages started with my kernel: 5.10.27 and FW: 20210511.
After breakage I jumped to a older kernel 5.4.97 and compiled 5.12.4. I 
didn't notice a breakage on 5.4.97 but system ran ~40 minutes.
So I booted to newly compiled 5.12.4 where I was ~1h and it broke.
After that I booted to 5.4.97 again and downgraded my FW.
While I'm writing this I'm booted to kernel: 5.12.4 with FW: 20210315.

I also described my situation on the Gentoo bugzilla: 
https://bugs.gentoo.org/790566

"dmesg.log" attached here is from the time machine run fine (at the 
moment); "errors_sat_may_15_072825_pm_cest_2021.log" is a dmesg log from 
the time system broke

Can I get any help with this? What are the next steps I should take? Any 
other files I should provide?

-- 
Have a great day!

~ XGQT