Vbox安装增强功能出错

vbox安装增强功能出错
$ sudo yum install -y kernel-devel gcc
$ mkdir /home/VirtualBoxGuestAdditions
$ mount -r /dev/cdrom /media/VirtualBoxGuestAdditions
$ cd /media
$ cd VirtualBoxGuestAdditions
$ sh ./VBoxLniuxAdditions.run
$ yum -y install bzip2
$ reboot