KVM / QEMU: VGA Passthrough

# Hardware:
i7 4771
ASRock Z87 Extreme6
AMD HD6950 1GB
# Software:
Kubuntu 14.04
QEMU emulator version 1.7.91 (Debian 2.0.0~rc1+dfsg-0ubuntu2)
Linux 3.14.0-999-generic (kernel . ubuntu . com/~kernel-ppa/mainline/daily/2014-04-08-trusty/)

----------------------------------- /etc/modules
blacklist radeon
pci-stub
vfio-pci
vfio-iommu-type1 allow_unsafe_interrupts=1
pci-stub ids=1002:6719,1002:aa80,8086:1539
----------------------------------- /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="intel_iommu=on pci-stub.ids=1002:6719,1002:aa80,8086:1539 vfio_iommu_type1.allow_unsafe_interrupts=1 quiet splash"

-----------------------------------
BEFORE EVERYTHING:
# ethernet
echo "8086 1539" > /sys/bus/pci/drivers/pci-stub/new_id
echo 0000:04:00.0 > /sys/bus/pci/devices/0000:04:00.0/driver/unbind
echo 0000:04:00.0 > /sys/bus/pci/drivers/pci-stub/bind
echo "8086 1539" > /sys/bus/pci/drivers/pci-stub/remove_id

--------------------- ONE: RUN pci-assign:

echo "1002 6719" > /sys/bus/pci/drivers/pci-stub/new_id
echo "0000:01:00.0" > /sys/bus/pci/devices/0000:01:00.0/driver/unbind
echo "0000:01:00.0" > /sys/bus/pci/drivers/pci-stub/bind
echo "1002 6719" > /sys/bus/pci/drivers/pci-stub/remove_id

echo "1002 aa80" > /sys/bus/pci/drivers/pci-stub/new_id
echo 0000:01:00.1 > /sys/bus/pci/devices/0000:01:00.1/driver/unbind
echo 0000:01:00.1 > /sys/bus/pci/drivers/pci-stub/bind
echo "1002 aa80" > /sys/bus/pci/drivers/pci-stub/remove_id


qemu-system-x86_64 \
-bios /usr/share/qemu/bios.bin \
-boot menu=on \
-enable-kvm \
-vga qxl \
\
-m 4G \
-cpu host \
-smp 6,sockets=1,cores=6,threads=1 \
-device pci-assign,host=04:00.0,rombar=0 \
-soundhw hda \
\
-name "win81_pci_assign" \
-M pc-1.3 \
\
-drive file=/opt/vm/test.qcow2,id=disk,format=qcow2,if=virtio,cache=writethrough,aio=native \
\
-device pci-assign,host=01:00.0,id=hostpci0



--------------------- TWO: RUN vfio-pci:
echo "0000:01:00.0" > /sys/bus/pci/devices/0000:01:00.0/driver/unbind
echo "0000:01:00.0" > /sys/bus/pci/drivers/vfio-pci/bind
echo 0000:01:00.1 > /sys/bus/pci/devices/0000:01:00.1/driver/unbind
echo 0000:01:00.1 > /sys/bus/pci/drivers/vfio-pci/bind

qemu-system-x86_64 \
-bios /usr/share/qemu/bios.bin \
-boot menu=on \
-enable-kvm \
-vga qxl \
\
-m 4G \
-cpu host \
-smp 6,sockets=1,cores=6,threads=1 \
-device pci-assign,host=04:00.0,rombar=0 \
-soundhw hda \
\
-name "win81_vfio_pci" \
-M q35 \
\
-drive file=/opt/vm/test.qcow2,id=disk,format=qcow2 \
-device ide-hd,bus=ide.0,drive=disk \
\
-device ioh3420,bus=pcie.0,addr=1c.0,multifunction=on,port=1,chassis=1,id=root.1 \
-device vfio-pci,host=01:00.0,bus=root.1,addr=00.0,multifunction=on,x-vga=on



--------------------- THREE: RESET GPU with vfio-pci:
echo "0000:01:00.0" > /sys/bus/pci/devices/0000:01:00.0/driver/unbind
echo "0000:01:00.0" > /sys/bus/pci/drivers/vfio-pci/bind
echo 0000:01:00.1 > /sys/bus/pci/devices/0000:01:00.1/driver/unbind
echo 0000:01:00.1 > /sys/bus/pci/drivers/vfio-pci/bind

qemu-system-x86_64 \
-bios /usr/share/qemu/bios.bin \
-enable-kvm \
\
-m 512 \
-cpu host \
-smp 4,sockets=1,cores=4,threads=1 \
\
-M q35 \
\
-device ioh3420,bus=pcie.0,addr=1c.0,multifunction=on,port=1,chassis=1,id=root.1 \
-device vfio-pci,host=01:00.0,bus=root.1,addr=00.0,multifunction=on,x-vga=on \
-device vfio-pci,host=01:00.1,bus=root.1,addr=00.1