https://bugzilla.kernel.org/show_bug.cgi?id=204683
--- Comment #6 from Matthias Heinz (mh@familie-heinz.name) --- I had to switch to drm-next to do further bisecting and I think 634092b1b9f67bea23a87b77880df5e8012a411a is causing the problem.
I might be wrong though.