Kludgy bash code to determine if vfio-pci display option is supported and requires GL support

gistfile1.txt

#!/bin/sh

MLOCK=0

lspci -s $1 > /dev/null 2>&1
if [ $? -eq 0 ]; then
	# PCI device
	if [ $(lspci -s $1 | wc -l) -gt 1 ]; then
		echo "Ambiguous device: $1"
		exit 1
	fi

	PCI_DEV=$(lspci -Ds $1 | awk '{print $1}')
	OPT="host=$PCI_DEV"
	if [ ! -L /sys/bus/pci/devices/$PCI_DEV/iommu_group ]; then
		echo "No IOMMU group for device"
		exit 1
	fi

	GROUP=$(basename $(readlink -f /sys/bus/pci/devices/$PCI_DEV/iommu_group))
	MLOCK=1
else
	OPT="sysfsdev=$1"
	if [ ! -L $1/iommu_group ]; then
		echo "No IOMMU group for device"
		exit 1
	fi
	GROUP=$(basename $(readlink -f $1/iommu_group))
	SUBSYS=$(basename $(readlink -f $1/subsystem))
	if [ $SUBSYS != "mdev" ]; then
		MLOCK=1
	fi
fi

if [ $EUID -eq 0 ]; then
	MLOCK=0
fi

if [ $MLOCK -ne 0 ]; then
	if [ $(ulimit -l) -lt $(( 1024 * 1024 )) ]; then
		echo "Increase locked memory limit to 1MB for test"
		exit 1
	fi
fi

if [ ! -c /dev/vfio/$GROUP ]; then
	echo "No VFIO group for device"
	exit 1
fi

if [ ! -w /dev/vfio/$GROUP ]; then
	echo "No permissions to VFIO group"
	exit 1
fi

TMP=$(mktemp)

exec /usr/local/bin/qemu-system-x86_64 \
	-machine pc,accel=kvm \
	-uuid $(uuidgen) \
	-m 1 \
	-S \
	-no-user-config \
	-nodefaults \
	-M graphics=off \
	-display none \
	-device vfio-pci,$OPT,display=on \
	> $TMP 2>&1 &

PID=$!
sleep 1

if kill -0 $PID 2>/dev/null; then
	kill -TERM $PID
	wait
	echo "Display supported, GL NOT required"
else
	if grep -q "opengl not available" $TMP; then
		echo "Display supported, GL required"
	elif grep -q "device doesn't support any (known) display method" $TMP; then
		echo "Display NOT supported"
	else
		echo "Unknown failure"
	fi
fi

rm -f $TMP

exit 0