Created attachment 132118 [details]
journal_HDMI_detaching_corruption

> Without seeing the corresponding Xorg log, I guess that's just
> a different symptom triggered by the same issue.
Attached the log. Yeah, not much different.

> With an amd-staging-* kernel branch and DC enabled, you can try tweaking
> dce_v11_0_crtc_do_set_base to pass AMDGPU_GEM_DOMAIN_GTT instead of / in
> addition to AMDGPU_GEM_DOMAIN_VRAM to amdgpu_bo_pin. The DC code should
> already handle this correctly, but we're not sure whether or not there are
> additional constraints on system memory used for scanout. If there are, it
> probably won't work correctly yet.
I tried amd-staging-4.11 and interestingly dce_v11_0_crtc_do_set_base is called
only when DC is disabled. When DRM_AMD_DC=y the function is never called.

I tried also to make the s/AMDGPU_GEM_DOMAIN_VRAM/AMDGPU_GEM_DOMAIN_GTT/ change
with DC disabled. What I get is that I have some kind of intermittent display
corruption when _connecting_ the HDMI cable on both the screens but on
detaching at least everything is fine on the laptop panel.