Cannot Reboot Ubuntu 12.10 on Acer Laptop

I installed ubuntu 12.10 server edition 64bit. When I want to reboot the system, I got stuck.

After googled a lot, I got the answer:

sudo vi /etc/default/grub

edit the line

GRUB_CMDLINE_LINUX=””

to

GRUB_CMDLINE_LINUX=”reboot=efi”

then

sudo shutdown -P now

and start the laptop.

Now, I can reboot correctly.