diff --git a/sig.c b/sig.c
index 2dd5b5ac..a030d581 100644
--- a/sig.c
+++ b/sig.c
@@ -159,6 +159,7 @@ void do_shutdown(shutop_t op)
 	unmount_regular();
 
 	/* We sit on / so we must remount it ro, try all the things! */
+	run("sync");
 	run("/bin/mount -n -o remount,ro -t dummytype dummydev /");
 	run("/bin/mount -n -o remount,ro dummydev /");
 	run("/bin/mount -n -o remount,ro /");