I had sever issues this morning after last night’s upgrade from Ubuntu Jaunty to Koala. Xorg was constantly at 98%, sound was broken, and the whole system was completely unresponsive.
Looking in /boot/grub/menu.lst I noticed the upgrade hadn’t actually added the new kernel at all. So I copied to config for the previous kernel and updated it to the new 2.6.31-14 kernel and on reboot we have sound and Xorg is now playing nicely at about 2% CPU. Panic over.
1title Ubuntu 9.10, kernel 2.6.31-14-generic 2root (hd0,0) 3kernel /boot/vmlinuz-2.6.31-14-generic root=UUID=a3c5e83c-f5f2-4704-8bd9-530ecf71f9e5 ro quiet splash acpi_osi="Linux" 4initrd /boot/initrd.img-2.6.31-14-generic 5quiet 6 7title Ubuntu 9.04, kernel 2.6.28-11-generic 8root (hd0,0) 9kernel /boot/vmlinuz-2.6.28-11-generic root=UUID=a3c5e83c-f5f2-4704-8bd9-530ecf71f9e5 ro quiet splash acpi_osi="Linux" 10initrd /boot/initrd.img-2.6.28-11-generic 11quiet