diff --git a/bootchartd.in b/bootchartd.in
index 3030ac2..a0c8ea8 100755
--- a/bootchartd.in
+++ b/bootchartd.in
@@ -104,6 +104,11 @@ wait_boot()
 {
 	trap "" HUP
 
+	# With no EXIT_PROC configured there is nothing to watch
+	# for. Bail out and let collection be stopped externally
+	# instead.
+	[ -n "$EXIT_PROC" ] || return
+
 	# Wait for /proc first - without it we have issues
 	while [ ! -e /proc/cmdline ]; do
 		$USLEEP 50000