https://bugs.freedesktop.org/show_bug.cgi?id=98915
--- Comment #3 from Nicolai Stange nicstange@gmail.com --- (In reply to Alex Deucher from comment #2)
Can you bisect?
No need: most likely, the offending commit is 8a357d10043c ("drm: Nerf DRM_CONTROL nodes").
C.f. the discussion at http://lkml.kernel.org/r/20161203144700.2307-1-nicstange@gmail.com
A patch for amdgpu is in the works as well.