Created attachment 396936 [details] X + kernel log How to produce the bug: 1) Closing lid to sleep 2) Opening lid. 3) Screen remains black (not active). Keyboard lights are on, hard disk is active. Everything seems to run except the display is black. 4) I can also switch to VT with Ctrl-Alt-F[123]. Switching back to X Ctrl-Alt-F7 returns to the black screen. 5) I can re-activate the screen by restarting X with systemctl restart gdm. This bug is not always triggered. It seems more likely to be triggered when I am plugged in to a docking station before going to sleep. That includes power but also another monitor. The laptop is a Dell Latitude e6520. Some similarity to Bug 269663 and Bug 290693, but - I do not use x11-drivers/nvidia-drivers - I do not use x11-drivers/nvidia-drivers - Instead I use x11-drivers/xf86-video-nouveau 1.0.10 Please let me know what other information you need.
Created attachment 396938 [details] emerge --info
Some suspicious log entries include gnome-session[...]: (gnome-settings-daemon:...): GnomeDesktop-WARNING **: Error setting property 'PowerSaveMode' on interface org.gnome.Mutter.DisplayConfig: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.gnome.Mutter.DisplayConfig was not provided by any .service files (g-dbus-error-quark, 2) XKEYBOARD keymap compiler (xkbcomp) reports: Warning: Type "ONE_LEVEL" has 1 levels, but <RALT> has 2 symbols; Ignoring extra symbols http://en.community.dell.com/support-forums/laptop/f/3519/t/19498672 suggest it is a driver problem (not firmware). This bug https://bugs.launchpad.net/ubuntu/+source/gnome-power-manager/+bug/455129 forwards to https://bugzilla.gnome.org/show_bug.cgi?id=607850 but in my case, going to sleep (either by closing the lid or Fn-F1) and waking up again does not resolve the problem.
Your kernel log is very incomplete, it does not contain any of the early boot messages. Try upgrading to kernel 3.19 and xf86-video-nouveau-1.0.11 if you have not already.
Please try again with latest versions and report back if it still fails.
I do not own that laptop anymore, sorry, so I can not reproduce this bug.
