Comment # 2 on bug 96532 from George Spelvin

Confirmed fixed in v4.7-rc5.  Fixed by this patch (in v4.7-rc3):

commit fffc5f59f2c68ca859c3f92b224393ed3adbe1ca
Author: Philipp Zabel <p.zabel@pengutronix.de>
Date:   Thu Jun 2 19:27:51 2016 +0200

    drm/crtc: fix connector reference counting mismatch in
drm_crtc_helper_set_config

Duplicate of
https://bugzilla.kernel.org/show_bug.cgi?id=119861