Created attachment 108632 [details]
journalctl -b (via ssh) with excerpts from suspend and resume

Dell M4800 with QHD+ display -- NVIDIA Corporation GK106GLM [Quadro K2100M]
(rev a1), 3.16.6-gentoo.

systemctl suspend works cleanly and quickly. Resume (power button), not so
much:

   09:33:43 kernel: nouveau E[     DRM] GPU lockup - switching to software
fbcon
   09:33:58 kernel: nouveau E[ X[4664]] failed to idle channel 0xcccc0000
[X[4664]]

...lots more. See attachment. X screen flashes briefly but is unusable and
corrupt (color bars, blocks offset/shifted, no cursor anyway).

This is on a good boot (ref bug 85495).