Hi Harry, A kernel bug report was opened against Ubuntu [0]. After a kernel bisect, it was found the following commit introduced the bug: commit 4562236b3bc0a28aeb6ee93b2d8a849a4c4e1c7c Author: Harry Wentland <harry.wentland at amd.com> Date:  Tue Sep 12 15:58:20 2017 -0400    drm/amd/dc: Add dc display driver (v2) The regression was introduced as of v4.15-rc1 and still exists in current mainline. The commit does not need to be reverted to resolve the bug. Disabling the CONFIG_DRM_AMD_DC_PRE_VEGA option makes the bug go away.    I was hoping to get your feedback, since you are the patch author. Do you think gathering any additional data will help diagnose this issue?    Thanks, Joe [0] http://pad.lv/1761751