Merge pull request #10732 from microsoft/danmihai/minor-systemd-cleanup

rootfs: minor systemd file deletion cleanup

tools/osbuilder/rootfs-builder/rootfs.sh

@@ -66,6 +66,29 @@ if [ "${CROSS_BUILD}" == "true" ]; then
 	fi
 fi
 
+# The list of systemd units and files that are not needed in Kata Containers
+readonly -a systemd_units=(
+	"systemd-coredump@"
+	"systemd-journald"
+	"systemd-journald-dev-log"
+	"systemd-journal-flush"
+	"systemd-random-seed"
+	"systemd-timesyncd"
+	"systemd-tmpfiles-setup"
+	"systemd-udevd"
+	"systemd-udevd-control"
+	"systemd-udevd-kernel"
+	"systemd-udev-trigger"
+	"systemd-update-utmp"
+)
+
+readonly -a systemd_files=(
+	"systemd-bless-boot-generator"
+	"systemd-fstab-generator"
+	"systemd-getty-generator"
+	"systemd-gpt-auto-generator"
+	"systemd-tmpfiles-cleanup.timer"
+)
 
 handle_error() {
 	local exit_code="${?}"
@@ -768,6 +791,8 @@ EOF
 	info "Create /etc/resolv.conf file in rootfs if not exist"
 	touch "$dns_file"
 
+	delete_unnecessary_files
+
 	info "Creating summary file"
 	create_summary_file "${ROOTFS_DIR}"
 }
@@ -807,6 +832,27 @@ detect_host_distro()
 	esac
 }
 
+delete_unnecessary_files()
+{
+	info "Removing unneeded systemd services and sockets"
+	for u in "${systemd_units[@]}"; do
+		find "${ROOTFS_DIR}" \
+			\( -type f -o -type l \) \
+			\( -name "${u}.service" -o -name "${u}.socket" \) \
+			-exec echo "deleting {}" \; \
+			-exec rm -f {} \;
+	done
+
+	info "Removing unneeded systemd files"
+	for u in "${systemd_files[@]}"; do
+		find "${ROOTFS_DIR}" \
+			\( -type f -o -type l \) \
+			-name "${u}" \
+			-exec echo "deleting {}" \; \
+			-exec rm -f {} \;
+	done
+}
+
 main()
 {
 	parse_arguments $*