qemu-system-arm -enable-kvm -M vexpress-a9 -drive file=/arm-whee
zy.img,if=virtio,cache=writeback -append 'root=/dev/mmcblk0 console=ttyAMA1 root
wait earlyprintk' -kernel /zImage-guest -nographic
qemu-system-arm: -drive file=/arm-wheezy.img,if=virtio,cache=writeback: No 'PCI' bus found for device 'virtio-blk-pci'