QEMU显示虚拟化的几种选项
QEMU可以通过通过命令行"-vga type"选择为客户机模拟的VGA卡的类别，可选择的类型有多个：
-vga type
Select type of VGA card to emulate. Valid values for type are
cirrus
Cirrus Logic GD5446 Video card. All Windows versions starting from Windows 95 should recognize and use this graphic card. For optimal performances, use 16 bit color depth in the guest
and the host OS. (This card was the default before QEMU 2.2)
std Standard VGA card with Bochs VBE extensions. If your guest OS supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want to use high resolution modes (>= 1280x1024x16)
then you should use this option. (This card is the default since QEMU 2.2)
vmware
VMWare SVGA-II compatible adapter. Use it if you have suffici