icsk->icsk_mtup.probe_size = 0;
 }
 
-static void tcp_mtup_probe_success(struct sock *sk, struct sk_buff *skb)
+static void tcp_mtup_probe_success(struct sock *sk)
 {
        struct tcp_sock *tp = tcp_sk(sk);
        struct inet_connection_sock *icsk = inet_csk(sk);
                        acked_pcount = tcp_skb_pcount(skb);
                }
 
-               /* MTU probing checks */
-               if (fully_acked && icsk->icsk_mtup.probe_size &&
-                   !after(tp->mtu_probe.probe_seq_end, scb->end_seq)) {
-                       tcp_mtup_probe_success(sk, skb);
-               }
-
                if (sacked & TCPCB_RETRANS) {
                        if (sacked & TCPCB_SACKED_RETRANS)
                                tp->retrans_out -= acked_pcount;
                const struct tcp_congestion_ops *ca_ops
                        = inet_csk(sk)->icsk_ca_ops;
 
+               if (unlikely(icsk->icsk_mtup.probe_size &&
+                            !after(tp->mtu_probe.probe_seq_end, tp->snd_una))) {
+                       tcp_mtup_probe_success(sk);
+               }
+
                tcp_ack_update_rtt(sk, flag, seq_rtt);
                tcp_rearm_rto(sk);