diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 65f80c7..4d8ce93 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -767,8 +767,8 @@
 	return i;
 }
 
-static unsigned long num_arg(const char __user * user_buffer,
-			     unsigned long maxlen, unsigned long *num)
+static long num_arg(const char __user *user_buffer, unsigned long maxlen,
+				unsigned long *num)
 {
 	int i;
 	*num = 0;