Ubuntu – Blank screen after suspend/hibernate on 14.04

This is pretty clearly a bug and not something that should have to be worked around or which could be fixed through user action. The best thing to do in these cases is to open a bug in launchpad so that Ubuntu developers can see it and track it.

For suspend/resume or hibernate problems, it's best to open the bug against the linux kernel. You can do that from a shell by typing:

ubuntu-bug linux

A lot of graphic resume problems could be solved by doing the suspend/resume from the virtual console, so that after the resume a "refresh" is forced by the graphic drivers.

Check if the system suspend correctly from a virtual console:

1. switch to a virtual console with CtrlAltF1

2. login with your user and password

3. suspend the system (either using the suspend key-combo for your system, or issuing the command sudo /usr/sbin/pm-suspend)

4. resume -> you should have a working prompt (exactly the same screens as before), otherwise see FAIL

5. switch to the graphic console with CtrlAltF7

6. if all is ok, problem solved! You can follow the instruction below (from this answer) to make the switch automatic; otherwise, see FAIL

If something is still wrong...

FAIL: So the problem is another one --- I do not have that laptop so I can't really help a lot more. Maybe studying the content of file /var/log/pm-suspend.log can shed some light.

1. edit/create the file

   gksudo gedit /etc/pm/sleep.d/01_switchvt

2. Put this content in it:

   #!/bin/sh
   
   # Switch to a VC before suspending and back after resume
   
   case "$1" in
       resume|thaw)
           chvt 7
       ;;
       suspend|hibernate)
           chvt 1
       ;;
   esac
   

3. save and exit

4. make it executable:

   sudo chmod 755 /etc/pm/sleep.d/01_switchvt

Notice in step 2, most of the installations will need the command chvt 7 --- this is the same as pushing ctrl-alt-F7 to go back to the graphic screen. If you need another key combo, change the "7" there accordingly.