I guess, there are plenty of duplicates of this question, but I didn't find any to be helpful in my particular problem.
My story is as follows: I was running Xubuntu 12.04 on a Thinkpad X40 which has an Intel 855GM graphics chip. On 12.04 suspend worked flawless. Yesterday I upgraded to 14.04 and this broke suspend. The problem is like this: I close the lid, the laptop goes to sleep. After some time I open the lid, the screen goes on and if I'm fast I can even start typing in the password. However some seconds later the screen switches off again, though I can hear that the system continues working. I can still switch to any TTY, only X has no graphical output. If I kill X from TTY, it starts again, I can login and then the system works as expected. In /var/log/Xorg.0.log I see following lines:
(II) AIGLX: Suspending AIGLX clients for VT switch
(II) AIGLX: Resuming AIGLX clients after VT switch
(II) AIGLX: Suspending AIGLX clients for VT switch
which exactly fits to my observations: On lid close the screen goes off, on opening the lid it goes on and then after some seconds off again.
Any thoughts on how to prevent X from switching off the screen after waking up?
Thanks for any input.
Bug reported: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1310038
As somebody pointed out in an answer that seems deleted now, a workaround is to switch off light locker.
Here are a few options to avoid or recover from the issue.
Temporary fix
In the main bug ticket there's now a fix which involves adding a PPA:
Add the Xubuntu Developers PPA to get the new packages: sudo add-apt-repository ppa:xubuntu-dev/ppa
Update package information and update the two crucial packages:
sudo apt-get update && sudo apt-get install xfce4-power-manager light-locker-settings
xfce4-power-manager-data will get upgraded at the same time
Restart your machine.
To remove the upgrades and return your machine to it's state prior to testing
sudo ppa-purge ppa:xubuntu-dev/ppa
Temporary workaround
The easiest way to work around this bug is to disable lock on suspend in the light locker settings. Of course, this means that your machine will resume from suspend without a password.
Quick fix
If you end up in this situation you can get back to a working state (note that you'll lose your current session and a new one will be started) by:
sudo service lightdm restart이 기사는 인터넷에서 수집됩니다. 재 인쇄 할 때 출처를 알려주십시오.
침해가 발생한 경우 연락 주시기 바랍니다[email protected] 삭제
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