Kernel 4.9-rc1 fails on shutdown/reboot with a panic. Bisect pointed me to 

00ea8cba5ef7b783f11cb1a0b900b7c18d2ce0b6 is the first bad commit
commit 00ea8cba5ef7b783f11cb1a0b900b7c18d2ce0b6
Author: Alex Deucher <alexander.deucher@amd.com>
Date:   Thu Sep 22 14:40:29 2016 -0400

    drm/amdgpu: always apply pci shutdown callbacks (v2)

    We can't properly detect all hypervisors and we
    need this to properly tear down the hardware.

    v2: trivial warning fix

    Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

:040000 040000 868a00ff980f95dac82b908df0737342bf40cdc3
02bf2cf4e8797d37d454301afedf2f97735b60ca M      drivers

After removing this commit, everything works again. System is a Carrizo.