Unable to shutdown, restart or log out

I have been unable to restart, shutdown, or log out of ubuntu since the release of 12.04. I have upgrade at the time of release for 12.10 and now for 13.04 and have had no change in the situation. On logout or restart i get a solid black screen where it just sits.

I have let it sit for long periods and I get a message every 2 minutes or so stating something about Xorg blocked for 120seconds. I have search extensively and can't find anything that actually fixes it. Using the shutdown now command works from terminal with -P -r. Updating grub had no effect. Any clues or help would be great.

Solution 1:

Ok, this is usually a hardware issue but could be drivers. Normally if you see it related it X it's a stale video driver. Try updating your video drivers. Finally you can always

echo 0 > /proc/sys/kernel/hung_task_timeout_secs

This will effectively quite is symptom but the problem will remain. This is certainly related to either failing hardware or bad drivers. The fact that you can actaully reboot via command line leads me to believe that it's a bad video driver. Make sure your running the latest video driver and that when you upgraded to 12.04 you kept using the same driver you were using when it was working (open v.s. propitiatory).

Another thing to look at is making sure you don't have any network shares mounted. When you log out of X network manager terminates a wireless connection. This will cause the system to hang for several minuets per file system read. During shutdown this can be quite a lengthy process. The quick test/fix is make sure all remote shares are unmounted before logging out. If that is the case then you should try adjusting your mount commands to show that they are network mounts and should be unmounted before you turn off the wifi connection. This varies by file system and mount type.