tools/testing/selftests/bpf/vmtest.sh - linux - Git at Google

 #!/bin/bash
 # SPDX-License-Identifier: GPL-2.0

 set -u
 set -e

 # This script currently only works for x86_64, as
 # it is based on the VM image used by the BPF CI which is
 # x86_64.
 QEMU_BINARY="${QEMU_BINARY:="qemu-system-x86_64"}"
 X86_BZIMAGE="arch/x86/boot/bzImage"
 DEFAULT_COMMAND="./test_progs"
 MOUNT_DIR="mnt"
 ROOTFS_IMAGE="root.img"
 OUTPUT_DIR="$HOME/.bpf_selftests"
 KCONFIG_URL="https://raw.githubusercontent.com/libbpf/libbpf/master/travis-ci/vmtest/configs/latest.config"
 KCONFIG_API_URL="https://api.github.com/repos/libbpf/libbpf/contents/travis-ci/vmtest/configs/latest.config"
 INDEX_URL="https://raw.githubusercontent.com/libbpf/libbpf/master/travis-ci/vmtest/configs/INDEX"
 NUM_COMPILE_JOBS="$(nproc)"
 LOG_FILE_BASE="$(date +"bpf_selftests.%Y-%m-%d_%H-%M-%S")"
 LOG_FILE="${LOG_FILE_BASE}.log"
 EXIT_STATUS_FILE="${LOG_FILE_BASE}.exit_status"

 usage()
 {
 	cat <<EOF
 Usage: $0 [-i] [-s] [-d <output_dir>] -- [<command>]

 <command> is the command you would normally run when you are in
 tools/testing/selftests/bpf. e.g:

 	$0 -- ./test_progs -t test_lsm

 If no command is specified and a debug shell (-s) is not requested,
 "${DEFAULT_COMMAND}" will be run by default.

 If you build your kernel using KBUILD_OUTPUT= or O= options, these
 can be passed as environment variables to the script:

   O=<kernel_build_path> $0 -- ./test_progs -t test_lsm

 or

   KBUILD_OUTPUT=<kernel_build_path> $0 -- ./test_progs -t test_lsm

 Options:

 	-i)		Update the rootfs image with a newer version.
 	-d)		Update the output directory (default: ${OUTPUT_DIR})
 	-j)		Number of jobs for compilation, similar to -j in make
 			(default: ${NUM_COMPILE_JOBS})
 	-s)		Instead of powering off the VM, start an interactive
 			shell. If <command> is specified, the shell runs after
 			the command finishes executing
 EOF
 }

 unset URLS
 populate_url_map()
 {
 	if ! declare -p URLS &> /dev/null; then
 		# URLS contain the mapping from file names to URLs where
 		# those files can be downloaded from.
 		declare -gA URLS
 		while IFS=$'\t' read -r name url; do
 			URLS["$name"]="$url"
 		done < <(curl -Lsf ${INDEX_URL})
 	fi
 }

 download()
 {
 	local file="$1"

 	if [[ ! -v URLS[$file] ]]; then
 		echo "$file not found" >&2
 		return 1
 	fi

 	echo "Downloading $file..." >&2
 	curl -Lsf "${URLS[$file]}" "${@:2}"
 }

 newest_rootfs_version()
 {
 	{
 	for file in "${!URLS[@]}"; do
 		if [[ $file =~ ^libbpf-vmtest-rootfs-(.*)\.tar\.zst$ ]]; then
 			echo "${BASH_REMATCH[1]}"
 		fi
 	done
 	} | sort -rV | head -1
 }

 download_rootfs()
 {
 	local rootfsversion="$1"
 	local dir="$2"

 	if ! which zstd &> /dev/null; then
 		echo 'Could not find "zstd" on the system, please install zstd'
 		exit 1
 	fi

 	download "libbpf-vmtest-rootfs-$rootfsversion.tar.zst" |
 		zstd -d | sudo tar -C "$dir" -x
 }

 recompile_kernel()
 {
 	local kernel_checkout="$1"
 	local make_command="$2"

 	cd "${kernel_checkout}"

 	${make_command} olddefconfig
 	${make_command}
 }

 mount_image()
 {
 	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"
 	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"

 	sudo mount -o loop "${rootfs_img}" "${mount_dir}"
 }

 unmount_image()
 {
 	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"

 	sudo umount "${mount_dir}" &> /dev/null
 }

 update_selftests()
 {
 	local kernel_checkout="$1"
 	local selftests_dir="${kernel_checkout}/tools/testing/selftests/bpf"

 	cd "${selftests_dir}"
 	${make_command}

 	# Mount the image and copy the selftests to the image.
 	mount_image
 	sudo rm -rf "${mount_dir}/root/bpf"
 	sudo cp -r "${selftests_dir}" "${mount_dir}/root"
 	unmount_image
 }

 update_init_script()
 {
 	local init_script_dir="${OUTPUT_DIR}/${MOUNT_DIR}/etc/rcS.d"
 	local init_script="${init_script_dir}/S50-startup"
 	local command="$1"
 	local exit_command="$2"

 	mount_image

 	if [[ ! -d "${init_script_dir}" ]]; then
 		cat <<EOF
 Could not find ${init_script_dir} in the mounted image.
 This likely indicates a bad rootfs image, Please download
 a new image by passing "-i" to the script
 EOF
 		exit 1

 	fi

 	sudo bash -c "echo '#!/bin/bash' > ${init_script}"

 	if [[ "${command}" != "" ]]; then
 		sudo bash -c "cat >>${init_script}" <<EOF
 # Have a default value in the exit status file
 # incase the VM is forcefully stopped.
 echo "130" > "/root/${EXIT_STATUS_FILE}"

 {
 	cd /root/bpf
 	echo ${command}
 	stdbuf -oL -eL ${command}
 	echo "\$?" > "/root/${EXIT_STATUS_FILE}"
 } 2>&1 | tee "/root/${LOG_FILE}"
 # Ensure that the logs are written to disk
 sync
 EOF
 	fi

 	sudo bash -c "echo ${exit_command} >> ${init_script}"
 	sudo chmod a+x "${init_script}"
 	unmount_image
 }

 create_vm_image()
 {
 	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"
 	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"

 	rm -rf "${rootfs_img}"
 	touch "${rootfs_img}"
 	chattr +C "${rootfs_img}" >/dev/null 2>&1 || true

 	truncate -s 2G "${rootfs_img}"
 	mkfs.ext4 -q "${rootfs_img}"

 	mount_image
 	download_rootfs "$(newest_rootfs_version)" "${mount_dir}"
 	unmount_image
 }

 run_vm()
 {
 	local kernel_bzimage="$1"
 	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"

 	if ! which "${QEMU_BINARY}" &> /dev/null; then
 		cat <<EOF
 Could not find ${QEMU_BINARY}
 Please install qemu or set the QEMU_BINARY environment variable.
 EOF
 		exit 1
 	fi

 	${QEMU_BINARY} \
 		-nodefaults \
 		-display none \
 		-serial mon:stdio \
 		-cpu host \
 		-enable-kvm \
 		-smp 8 \
 		-m 4G \
 		-drive file="${rootfs_img}",format=raw,index=1,media=disk,if=virtio,cache=none \
 		-kernel "${kernel_bzimage}" \
 		-append "root=/dev/vda rw console=ttyS0,115200"
 }

 copy_logs()
 {
 	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"
 	local log_file="${mount_dir}/root/${LOG_FILE}"
 	local exit_status_file="${mount_dir}/root/${EXIT_STATUS_FILE}"

 	mount_image
 	sudo cp ${log_file} "${OUTPUT_DIR}"
 	sudo cp ${exit_status_file} "${OUTPUT_DIR}"
 	sudo rm -f ${log_file}
 	unmount_image
 }

 is_rel_path()
 {
 	local path="$1"

 	[[ ${path:0:1} != "/" ]]
 }

 update_kconfig()
 {
 	local kconfig_file="$1"
 	local update_command="curl -sLf ${KCONFIG_URL} -o ${kconfig_file}"
 	# Github does not return the "last-modified" header when retrieving the
 	# raw contents of the file. Use the API call to get the last-modified
 	# time of the kernel config and only update the config if it has been
 	# updated after the previously cached config was created. This avoids
 	# unnecessarily compiling the kernel and selftests.
 	if [[ -f "${kconfig_file}" ]]; then
 		local last_modified_date="$(curl -sL -D - "${KCONFIG_API_URL}" -o /dev/null | \
 			grep "last-modified" | awk -F ': ' '{print $2}')"
 		local remote_modified_timestamp="$(date -d "${last_modified_date}" +"%s")"
 		local local_creation_timestamp="$(stat -c %Y "${kconfig_file}")"

 		if [[ "${remote_modified_timestamp}" -gt "${local_creation_timestamp}" ]]; then
 			${update_command}
 		fi
 	else
 		${update_command}
 	fi
 }

 main()
 {
 	local script_dir="$(cd -P -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd -P)"
 	local kernel_checkout=$(realpath "${script_dir}"/../../../../)
 	# By default the script searches for the kernel in the checkout directory but
 	# it also obeys environment variables O= and KBUILD_OUTPUT=
 	local kernel_bzimage="${kernel_checkout}/${X86_BZIMAGE}"
 	local command="${DEFAULT_COMMAND}"
 	local update_image="no"
 	local exit_command="poweroff -f"
 	local debug_shell="no"

 	while getopts 'hskid:j:' opt; do
 		case ${opt} in
 		i)
 			update_image="yes"
 			;;
 		d)
 			OUTPUT_DIR="$OPTARG"
 			;;
 		j)
 			NUM_COMPILE_JOBS="$OPTARG"
 			;;
 		s)
 			command=""
 			debug_shell="yes"
 			exit_command="bash"
 			;;
 		h)
 			usage
 			exit 0
 			;;
 		\? )
 			echo "Invalid Option: -$OPTARG"
 			usage
 			exit 1
 			;;
 		: )
 			echo "Invalid Option: -$OPTARG requires an argument"
 			usage
 			exit 1
 			;;
 		esac
 	done
 	shift $((OPTIND -1))

 	if [[ $# -eq 0  && "${debug_shell}" == "no" ]]; then
 		echo "No command specified, will run ${DEFAULT_COMMAND} in the vm"
 	else
 		command="$@"
 	fi

 	local kconfig_file="${OUTPUT_DIR}/latest.config"
 	local make_command="make -j ${NUM_COMPILE_JOBS} KCONFIG_CONFIG=${kconfig_file}"

 	# Figure out where the kernel is being built.
 	# O takes precedence over KBUILD_OUTPUT.
 	if [[ "${O:=""}" != "" ]]; then
 		if is_rel_path "${O}"; then
 			O="$(realpath "${PWD}/${O}")"
 		fi
 		kernel_bzimage="${O}/${X86_BZIMAGE}"
 		make_command="${make_command} O=${O}"
 	elif [[ "${KBUILD_OUTPUT:=""}" != "" ]]; then
 		if is_rel_path "${KBUILD_OUTPUT}"; then
 			KBUILD_OUTPUT="$(realpath "${PWD}/${KBUILD_OUTPUT}")"
 		fi
 		kernel_bzimage="${KBUILD_OUTPUT}/${X86_BZIMAGE}"
 		make_command="${make_command} KBUILD_OUTPUT=${KBUILD_OUTPUT}"
 	fi

 	populate_url_map

 	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"
 	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"

 	echo "Output directory: ${OUTPUT_DIR}"

 	mkdir -p "${OUTPUT_DIR}"
 	mkdir -p "${mount_dir}"
 	update_kconfig "${kconfig_file}"

 	recompile_kernel "${kernel_checkout}" "${make_command}"

 	if [[ "${update_image}" == "no" && ! -f "${rootfs_img}" ]]; then
 		echo "rootfs image not found in ${rootfs_img}"
 		update_image="yes"
 	fi

 	if [[ "${update_image}" == "yes" ]]; then
 		create_vm_image
 	fi

 	update_selftests "${kernel_checkout}" "${make_command}"
 	update_init_script "${command}" "${exit_command}"
 	run_vm "${kernel_bzimage}"
 	if [[ "${command}" != "" ]]; then
 		copy_logs
 		echo "Logs saved in ${OUTPUT_DIR}/${LOG_FILE}"
 	fi
 }

 catch()
 {
 	local exit_code=$1
 	local exit_status_file="${OUTPUT_DIR}/${EXIT_STATUS_FILE}"
 	# This is just a cleanup and the directory may
 	# have already been unmounted. So, don't let this
 	# clobber the error code we intend to return.
 	unmount_image || true
 	if [[ -f "${exit_status_file}" ]]; then
 		exit_code="$(cat ${exit_status_file})"
 	fi
 	exit ${exit_code}
 }

 trap 'catch "$?"' EXIT

 main "$@"
	#!/bin/bash
	# SPDX-License-Identifier: GPL-2.0

	set -u
	set -e

	# This script currently only works for x86_64, as
	# it is based on the VM image used by the BPF CI which is
	# x86_64.
	QEMU_BINARY="${QEMU_BINARY:="qemu-system-x86_64"}"
	X86_BZIMAGE="arch/x86/boot/bzImage"
	DEFAULT_COMMAND="./test_progs"
	MOUNT_DIR="mnt"
	ROOTFS_IMAGE="root.img"
	OUTPUT_DIR="$HOME/.bpf_selftests"
	KCONFIG_URL="https://raw.githubusercontent.com/libbpf/libbpf/master/travis-ci/vmtest/configs/latest.config"
	KCONFIG_API_URL="https://api.github.com/repos/libbpf/libbpf/contents/travis-ci/vmtest/configs/latest.config"
	INDEX_URL="https://raw.githubusercontent.com/libbpf/libbpf/master/travis-ci/vmtest/configs/INDEX"
	NUM_COMPILE_JOBS="$(nproc)"
	LOG_FILE_BASE="$(date +"bpf_selftests.%Y-%m-%d_%H-%M-%S")"
	LOG_FILE="${LOG_FILE_BASE}.log"
	EXIT_STATUS_FILE="${LOG_FILE_BASE}.exit_status"

	usage()
	{
	cat <<EOF
	Usage: $0 [-i] [-s] [-d <output_dir>] -- [<command>]

	<command> is the command you would normally run when you are in
	tools/testing/selftests/bpf. e.g:

	$0 -- ./test_progs -t test_lsm

	If no command is specified and a debug shell (-s) is not requested,
	"${DEFAULT_COMMAND}" will be run by default.

	If you build your kernel using KBUILD_OUTPUT= or O= options, these
	can be passed as environment variables to the script:

	O=<kernel_build_path> $0 -- ./test_progs -t test_lsm

	or

	KBUILD_OUTPUT=<kernel_build_path> $0 -- ./test_progs -t test_lsm

	Options:

	-i) Update the rootfs image with a newer version.
	-d) Update the output directory (default: ${OUTPUT_DIR})
	-j) Number of jobs for compilation, similar to -j in make
	(default: ${NUM_COMPILE_JOBS})
	-s) Instead of powering off the VM, start an interactive
	shell. If <command> is specified, the shell runs after
	the command finishes executing
	EOF
	}

	unset URLS
	populate_url_map()
	{
	if ! declare -p URLS &> /dev/null; then
	# URLS contain the mapping from file names to URLs where
	# those files can be downloaded from.
	declare -gA URLS
	while IFS=$'\t' read -r name url; do
	URLS["$name"]="$url"
	done < <(curl -Lsf ${INDEX_URL})
	fi
	}

	download()
	{
	local file="$1"

	if [[ ! -v URLS[$file] ]]; then
	echo "$file not found" >&2
	return 1
	fi

	echo "Downloading $file..." >&2
	curl -Lsf "${URLS[$file]}" "${@:2}"
	}

	newest_rootfs_version()
	{
	{
	for file in "${!URLS[@]}"; do
	if [[ $file =~ ^libbpf-vmtest-rootfs-(.*)\.tar\.zst$ ]]; then
	echo "${BASH_REMATCH[1]}"
	fi
	done
	} \| sort -rV \| head -1
	}

	download_rootfs()
	{
	local rootfsversion="$1"
	local dir="$2"

	if ! which zstd &> /dev/null; then
	echo 'Could not find "zstd" on the system, please install zstd'
	exit 1
	fi

	download "libbpf-vmtest-rootfs-$rootfsversion.tar.zst" \|
	zstd -d \| sudo tar -C "$dir" -x
	}

	recompile_kernel()
	{
	local kernel_checkout="$1"
	local make_command="$2"

	cd "${kernel_checkout}"

	${make_command} olddefconfig
	${make_command}
	}

	mount_image()
	{
	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"
	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"

	sudo mount -o loop "${rootfs_img}" "${mount_dir}"
	}

	unmount_image()
	{
	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"

	sudo umount "${mount_dir}" &> /dev/null
	}

	update_selftests()
	{
	local kernel_checkout="$1"
	local selftests_dir="${kernel_checkout}/tools/testing/selftests/bpf"

	cd "${selftests_dir}"
	${make_command}

	# Mount the image and copy the selftests to the image.
	mount_image
	sudo rm -rf "${mount_dir}/root/bpf"
	sudo cp -r "${selftests_dir}" "${mount_dir}/root"
	unmount_image
	}

	update_init_script()
	{
	local init_script_dir="${OUTPUT_DIR}/${MOUNT_DIR}/etc/rcS.d"
	local init_script="${init_script_dir}/S50-startup"
	local command="$1"
	local exit_command="$2"

	mount_image

	if [[ ! -d "${init_script_dir}" ]]; then
	cat <<EOF
	Could not find ${init_script_dir} in the mounted image.
	This likely indicates a bad rootfs image, Please download
	a new image by passing "-i" to the script
	EOF
	exit 1

	fi

	sudo bash -c "echo '#!/bin/bash' > ${init_script}"

	if [[ "${command}" != "" ]]; then
	sudo bash -c "cat >>${init_script}" <<EOF
	# Have a default value in the exit status file
	# incase the VM is forcefully stopped.
	echo "130" > "/root/${EXIT_STATUS_FILE}"

	{
	cd /root/bpf
	echo ${command}
	stdbuf -oL -eL ${command}
	echo "\$?" > "/root/${EXIT_STATUS_FILE}"
	} 2>&1 \| tee "/root/${LOG_FILE}"
	# Ensure that the logs are written to disk
	sync
	EOF
	fi

	sudo bash -c "echo ${exit_command} >> ${init_script}"
	sudo chmod a+x "${init_script}"
	unmount_image
	}

	create_vm_image()
	{
	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"
	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"

	rm -rf "${rootfs_img}"
	touch "${rootfs_img}"
	chattr +C "${rootfs_img}" >/dev/null 2>&1 \|\| true

	truncate -s 2G "${rootfs_img}"
	mkfs.ext4 -q "${rootfs_img}"

	mount_image
	download_rootfs "$(newest_rootfs_version)" "${mount_dir}"
	unmount_image
	}

	run_vm()
	{
	local kernel_bzimage="$1"
	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"

	if ! which "${QEMU_BINARY}" &> /dev/null; then
	cat <<EOF
	Could not find ${QEMU_BINARY}
	Please install qemu or set the QEMU_BINARY environment variable.
	EOF
	exit 1
	fi

	${QEMU_BINARY} \
	-nodefaults \
	-display none \
	-serial mon:stdio \
	-cpu host \
	-enable-kvm \
	-smp 8 \
	-m 4G \
	-drive file="${rootfs_img}",format=raw,index=1,media=disk,if=virtio,cache=none \
	-kernel "${kernel_bzimage}" \
	-append "root=/dev/vda rw console=ttyS0,115200"
	}

	copy_logs()
	{
	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"
	local log_file="${mount_dir}/root/${LOG_FILE}"
	local exit_status_file="${mount_dir}/root/${EXIT_STATUS_FILE}"

	mount_image
	sudo cp ${log_file} "${OUTPUT_DIR}"
	sudo cp ${exit_status_file} "${OUTPUT_DIR}"
	sudo rm -f ${log_file}
	unmount_image
	}

	is_rel_path()
	{
	local path="$1"

	[[ ${path:0:1} != "/" ]]
	}

	update_kconfig()
	{
	local kconfig_file="$1"
	local update_command="curl -sLf ${KCONFIG_URL} -o ${kconfig_file}"
	# Github does not return the "last-modified" header when retrieving the
	# raw contents of the file. Use the API call to get the last-modified
	# time of the kernel config and only update the config if it has been
	# updated after the previously cached config was created. This avoids
	# unnecessarily compiling the kernel and selftests.
	if [[ -f "${kconfig_file}" ]]; then
	local last_modified_date="$(curl -sL -D - "${KCONFIG_API_URL}" -o /dev/null \| \
	grep "last-modified" \| awk -F ': ' '{print $2}')"
	local remote_modified_timestamp="$(date -d "${last_modified_date}" +"%s")"
	local local_creation_timestamp="$(stat -c %Y "${kconfig_file}")"

	if [[ "${remote_modified_timestamp}" -gt "${local_creation_timestamp}" ]]; then
	${update_command}
	fi
	else
	${update_command}
	fi
	}

	main()
	{
	local script_dir="$(cd -P -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd -P)"
	local kernel_checkout=$(realpath "${script_dir}"/../../../../)
	# By default the script searches for the kernel in the checkout directory but
	# it also obeys environment variables O= and KBUILD_OUTPUT=
	local kernel_bzimage="${kernel_checkout}/${X86_BZIMAGE}"
	local command="${DEFAULT_COMMAND}"
	local update_image="no"
	local exit_command="poweroff -f"
	local debug_shell="no"

	while getopts 'hskid:j:' opt; do
	case ${opt} in
	i)
	update_image="yes"
	;;
	d)
	OUTPUT_DIR="$OPTARG"
	;;
	j)
	NUM_COMPILE_JOBS="$OPTARG"
	;;
	s)
	command=""
	debug_shell="yes"
	exit_command="bash"
	;;
	h)
	usage
	exit 0
	;;
	\? )
	echo "Invalid Option: -$OPTARG"
	usage
	exit 1
	;;
	: )
	echo "Invalid Option: -$OPTARG requires an argument"
	usage
	exit 1
	;;
	esac
	done
	shift $((OPTIND -1))

	if [[ $# -eq 0 && "${debug_shell}" == "no" ]]; then
	echo "No command specified, will run ${DEFAULT_COMMAND} in the vm"
	else
	command="$@"
	fi

	local kconfig_file="${OUTPUT_DIR}/latest.config"
	local make_command="make -j ${NUM_COMPILE_JOBS} KCONFIG_CONFIG=${kconfig_file}"

	# Figure out where the kernel is being built.
	# O takes precedence over KBUILD_OUTPUT.
	if [[ "${O:=""}" != "" ]]; then
	if is_rel_path "${O}"; then
	O="$(realpath "${PWD}/${O}")"
	fi
	kernel_bzimage="${O}/${X86_BZIMAGE}"
	make_command="${make_command} O=${O}"
	elif [[ "${KBUILD_OUTPUT:=""}" != "" ]]; then
	if is_rel_path "${KBUILD_OUTPUT}"; then
	KBUILD_OUTPUT="$(realpath "${PWD}/${KBUILD_OUTPUT}")"
	fi
	kernel_bzimage="${KBUILD_OUTPUT}/${X86_BZIMAGE}"
	make_command="${make_command} KBUILD_OUTPUT=${KBUILD_OUTPUT}"
	fi

	populate_url_map

	local rootfs_img="${OUTPUT_DIR}/${ROOTFS_IMAGE}"
	local mount_dir="${OUTPUT_DIR}/${MOUNT_DIR}"

	echo "Output directory: ${OUTPUT_DIR}"

	mkdir -p "${OUTPUT_DIR}"
	mkdir -p "${mount_dir}"
	update_kconfig "${kconfig_file}"

	recompile_kernel "${kernel_checkout}" "${make_command}"

	if [[ "${update_image}" == "no" && ! -f "${rootfs_img}" ]]; then
	echo "rootfs image not found in ${rootfs_img}"
	update_image="yes"
	fi

	if [[ "${update_image}" == "yes" ]]; then
	create_vm_image
	fi

	update_selftests "${kernel_checkout}" "${make_command}"
	update_init_script "${command}" "${exit_command}"
	run_vm "${kernel_bzimage}"
	if [[ "${command}" != "" ]]; then
	copy_logs
	echo "Logs saved in ${OUTPUT_DIR}/${LOG_FILE}"
	fi
	}

	catch()
	{
	local exit_code=$1
	local exit_status_file="${OUTPUT_DIR}/${EXIT_STATUS_FILE}"
	# This is just a cleanup and the directory may
	# have already been unmounted. So, don't let this
	# clobber the error code we intend to return.
	unmount_image \|\| true
	if [[ -f "${exit_status_file}" ]]; then
	exit_code="$(cat ${exit_status_file})"
	fi
	exit ${exit_code}
	}

	trap 'catch "$?"' EXIT

	main "$@"