On Carrizo unbinding  the driver will indeed show [drm:gfx_v8_0_hw_fini
[amdgpu]] *ERROR* KCQ disabled failed (scratch(0xC040)=0xCAFEDEAD), I don't
have LOCKDEP related kflags enabled in kernel for some reason so that probably
why I don't see the locking imbalance warning, will rebuild and check.

What card model are you using ?

Andrey