diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 677419d0c9ade7da761d5c558b9421b6e3e32f04..3e98b57578dc681b2386a2a007689d1b74979b48 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -2239,6 +2239,7 @@ static int tcp_ack_update_window(struct sock *sk, struct tcp_sock *tp,
 			/* Note, it is the only place, where
 			 * fast path is recovered for sending TCP.
 			 */
+			tp->pred_flags = 0;
 			tcp_fast_path_check(sk, tp);
 
 			if (nwin > tp->max_window) {