diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index 75de355a63d61b44413b6581ec620f61381458b3..10985d991ed29210457969dd5eb91bfb1dcf118a 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -2416,7 +2416,7 @@ static int arg_num_eval(struct print_arg *arg, long long *val)
 static char *arg_eval (struct print_arg *arg)
 {
 	long long val;
-	static char buf[20];
+	static char buf[24];
 
 	switch (arg->type) {
 	case PRINT_ATOM: