diff --git a/net/ipv4/tcp_probe.c b/net/ipv4/tcp_probe.c
index 1b72c55d336f506da8bf6359f54d2290d40d0d08..760165a0800c317884015f7997b3106aa7ad8562 100644
--- a/net/ipv4/tcp_probe.c
+++ b/net/ipv4/tcp_probe.c
@@ -80,7 +80,8 @@ static void printl(const char *fmt, ...)
 
 	kfifo_put(tcpw.fifo, tbuf, len);
 	wake_up(&tcpw.wait);
-}
+} __attribute__ ((format (printf, 1, 2)));
+
 
 /*
  * Hook inserted to be called before each receive packet.