KVM USB auto-passthrough using udev

90-libvirt-usb.rules

# File location: /etc/udev/rules.d/90-libvirt-usb.rules
ACTION=="bind", \
	SUBSYSTEM=="usb", \
	ENV{ID_VENDOR_ID}=="6b62", \
	ENV{ID_MODEL_ID}=="6869", \
	RUN+="/usr/local/bin/kvm-udev attach <domain>"
ACTION=="remove", \
	SUBSYSTEM=="usb", \
	ENV{ID_VENDOR_ID}=="6b62", \
	ENV{ID_MODEL_ID}=="6869", \
	RUN+="/usr/local/bin/kvm-udev detach <domain>"

kvm-udev.sh

#!/bin/bash

# File location: /usr/local/bin/kvm-udev.sh
# Usage: ./kvm-udev.sh attach|detach <domain>

set -e

ACTION=$1
DOMAIN=$2

CONF_FILE=$(mktemp --suffix=.kvm-udev)
cat << EOF >$CONF_FILE
<hostdev mode='subsystem' type='${SUBSYSTEM}'>
	<source>
		<vendor id='0x${ID_VENDOR_ID}' />
		<product id='0x${ID_MODEL_ID}' />
	</source>
</hostdev>
EOF

virsh "${ACTION}-device" "$DOMAIN" "$conf_file"
rm "$CONF_FILE"