1:查看当前安装的内核

dpkg -l|grep linux-image

2:安装内核

sudo apt-get install linux-image-extra-3.13.0-74-generic

3:卸载原有内核

sudo apt-get purge linux-image-3.13.0-xx-generic linux-image-extra-3.13.0-xx-generic

4:更新grub

sudo update-grub
sudo reboot