I changed my kernel to the linux-amd-staging-drm-next-git which already has patch applied. System boots, X starts fine, and I am able to run intensive 3d app without any performance/rendering issues, no special kernel commandline required. I get same error message as comment #19, but no “scrambled pixels.” NB For users with HP Envy x360 15m-bq1**** model laptops, the latest BIOS is F.20 which is not listed in the downloads section of HP support site, but rather under Advisories, https://support.hp.com/us-en/product/hp-envy-15m-bq100-x360-convertible-pc/16851057/model/18967057/document/c06219875 . NB2 For system stability, I added kernel option idle=nomwait which seems to have made the laptop far less crashy, YMMV.