diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index af3198814c15..9d504234af4a 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -345,6 +345,7 @@ static void svc_sock_setbufsize(struct socket *sock, unsigned int snd,
 	lock_sock(sock->sk);
 	sock->sk->sk_sndbuf = snd * 2;
 	sock->sk->sk_rcvbuf = rcv * 2;
+	sock->sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK;
 	release_sock(sock->sk);
 #endif
 }
@@ -796,6 +797,23 @@ static int svc_tcp_recvfrom(struct svc_rqst *rqstp)
 		test_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags),
 		test_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags));
 
+	if (test_and_clear_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags))
+		/* sndbuf needs to have room for one request
+		 * per thread, otherwise we can stall even when the
+		 * network isn't a bottleneck.
+		 *
+		 * We count all threads rather than threads in a
+		 * particular pool, which provides an upper bound
+		 * on the number of threads which will access the socket.
+		 *
+		 * rcvbuf just needs to be able to hold a few requests.
+		 * Normally they will be removed from the queue
+		 * as soon a a complete request arrives.
+		 */
+		svc_sock_setbufsize(svsk->sk_sock,
+				    (serv->sv_nrthreads+3) * serv->sv_max_mesg,
+				    3 * serv->sv_max_mesg);
+
 	clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 
 	/* Receive data. If we haven't got the record length yet, get
@@ -1043,6 +1061,15 @@ static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
 
 		tcp_sk(sk)->nonagle |= TCP_NAGLE_OFF;
 
+		/* initialise setting must have enough space to
+		 * receive and respond to one request.
+		 * svc_tcp_recvfrom will re-adjust if necessary
+		 */
+		svc_sock_setbufsize(svsk->sk_sock,
+				    3 * svsk->sk_xprt.xpt_server->sv_max_mesg,
+				    3 * svsk->sk_xprt.xpt_server->sv_max_mesg);
+
+		set_bit(XPT_CHNGBUF, &svsk->sk_xprt.xpt_flags);
 		set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags);
 		if (sk->sk_state != TCP_ESTABLISHED)
 			set_bit(XPT_CLOSE, &svsk->sk_xprt.xpt_flags);
@@ -1112,14 +1139,8 @@ static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
 	/* Initialize the socket */
 	if (sock->type == SOCK_DGRAM)
 		svc_udp_init(svsk, serv);
-	else {
-		/* initialise setting must have enough space to
-		 * receive and respond to one request.
-		 */
-		svc_sock_setbufsize(svsk->sk_sock, 4 * serv->sv_max_mesg,
-					4 * serv->sv_max_mesg);
+	else
 		svc_tcp_init(svsk, serv);
-	}
 
 	dprintk("svc: svc_setup_socket created %p (inet %p)\n",
 				svsk, svsk->sk_sk);