按照http://blog.youkuaiyun.com/mal327/article/details/6442288的步骤一点儿点儿来的,不过第一次安装除了问题
mal11@mal11-VirtualBox:/media/VBOXADDITIONS_3.2.12_68302$ sudo ./VBoxLinuxAdditions-x86.run
Verifying archive integrity... All good.
Uncompressing VirtualBox 3.2.12 Guest Additions for Linux........
VirtualBox Guest Additions installer
Uninstalling old VirtualBox DKMS kernel modules ...done.
Building the VirtualBox Guest Additions kernel modules
Building the main Guest Additions module ...fail!
(Look at /var/log/vboxadd-install.log to find out what went wrong)
Installing the Window System drivers
Warning: unknown version of the X Window System installed. Not installing
X Window System drivers.
Installing graphics libraries and desktop services components ...done.
mal11@mal11-VirtualBox:/media/VBOXADDITIONS_3.2.12_68302$
于是又重新安装了一遍。...没看到..就已经重启回来了...