diff --git a/release/tools/vmimage.subr b/release/tools/vmimage.subr
--- a/release/tools/vmimage.subr
+++ b/release/tools/vmimage.subr
@@ -168,8 +168,10 @@
 
 vm_extra_pkg_rmcache() {
 	if [ -e ${DESTDIR}/usr/local/sbin/pkg ]; then
+		mount -t devfs devfs ${DESTDIR}/dev
 		chroot ${DESTDIR} ${EMULATOR} env ASSUME_ALWAYS_YES=yes \
 			/usr/local/sbin/pkg clean -y -a
+		umount_loop ${DESTDIR}/dev
 	fi
 
 	return 0