Qemu PCI pass-through

qemu_pci_pass_through.txt

How to use 'pci pass-through' to run Linux in Qemu accessing real Ath9k adapter
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# Boot kernel with 'intel_iommu=on'

# Unbind driver from the device and bind 'pci-stub' to it
echo "168c 0030" > /sys/bus/pci/drivers/pci-stub/new_id
echo 0000:0b:00.0 > /sys/bus/pci/devices/0000:0b:00.0/driver/unbind
echo 0000:0b:00.0 > /sys/bus/pci/drivers/pci-stub/bind

# Then just run
sudo qemu-system-i386 -m 1024 \
	-device pci-assign,host=0b:00.0,rombar=0 \
	-enable-kvm \
	-kernel $KERNEL \
	-hda $DISK \
	-boot c \
	-append "root=/dev/sda rw"

# In case of
qemu-system-i386: -device pci-assign,host=0b:00.0: Failed to assign device "(null)" : Operation not permitted
qemu-system-i386: -device pci-assign,host=0b:00.0: Device initialization failed.
qemu-system-i386: -device pci-assign,host=0b:00.0: Device 'kvm-pci-assign' could not be initialized

dmesg | tail
[  112.129138] kvm_iommu_map_guest: No interrupt remapping support, disallowing device assignment. Re-enble with "allow_unsafe_assigned_interrupts=1" module option.

# run
echo 1 > /sys/module/kvm/parameters/allow_unsafe_assigned_interrupts