Comment # 4 on bug 110671 from Tomas Bzatek

Created attachment 144252 [details]
dmesg drm.debug=0x1e (kernel 4.20.0-zen-g742adf1bca12-dirty)

For the record, this is a custom 4.20.0 kernel that is proven realiable.

Basically agd5f drm-next-4.21 branch at 674e78acae0dfb4beb5613
"drm/amd/display: Add fast path for cursor plane updates"