Comment 2 for bug 600724

The problem is caused by the DKMS-enabled packages available on the repository, namely 'samsung-backlight', 'easy-slow-down-manager' and 'phc-intel'. These packages should automatically rebuilt themself against a new installed kernel, but for some reason they don't.

I'll take a deeper look at them as soon as I can; in the meanwhile you can fix the problem by forcing their reinstallation.

Use a command like this to reinstall them, then reboot:

sudo apt-get install --reinstall samsung-backlight easy-slow-down-manager phc-intel