diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
index 94ea87bd231c..3ccbb42c171c 100644
--- a/arch/um/kernel/time.c
+++ b/arch/um/kernel/time.c
@@ -256,9 +256,9 @@ int setup_time_travel_start(char *str)
 	return 1;
 }
 
-__setup("time-travel-start", setup_time_travel_start);
+__setup("time-travel-start=", setup_time_travel_start);
 __uml_help(setup_time_travel_start,
-"time-travel-start=<seconds>\n"
+"time-travel-start=<nanoseconds>\n"
 "Configure the UML instance's wall clock to start at this value rather than\n"
 "the host's wall clock at the time of UML boot.\n");
 #endif