Created attachment 145917 [details]
dmesg of new sdma0 error while watching youtube with firefox, mainline kernel
5.3.9, padoka ppa mesa 19.3

Hi,

after installing and testing some configurations, amdgpu pro with amdvlk and
kernel 4.15 (working..) and getting back to radv, cause only radv has no
graphical issues with World of Tanks (wine + dxvk). 
I have another dmesg output....btw /etc/environment has "export
AMD_DEBUG=nodma" included and it works for me that i can use the pc for 1 or 2
hours...much better then before...

so the attachment has many infos from the hang including sdma0 failure...maybe
this helps...