diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index 0a7ed5b5e281..6c164dc9ee95 100644
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -1537,6 +1537,8 @@ process_flags(struct event *event, struct print_arg *arg, char **tok)
 	field = malloc_or_die(sizeof(*field));
 
 	type = process_arg(event, field, &token);
+	while (type == EVENT_OP)
+		type = process_op(event, field, &token);
 	if (test_type_token(type, token, EVENT_DELIM, ","))
 		goto out_free;