diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h
index 7440290f64ac..ddb7f94a9d06 100644
--- a/include/linux/sunrpc/svc_xprt.h
+++ b/include/linux/sunrpc/svc_xprt.h
@@ -67,6 +67,7 @@ struct svc_xprt {
 #define XPT_CACHE_AUTH	11		/* cache auth info */
 #define XPT_LOCAL	12		/* connection from loopback interface */
 #define XPT_KILL_TEMP   13		/* call xpo_kill_temp_xprt before closing */
+#define XPT_CONG_CTRL	14		/* has congestion control */
 
 	struct svc_serv		*xpt_server;	/* service for transport */
 	atomic_t    	    	xpt_reserved;	/* space on outq that is rsvd */
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index de066acdb34e..1956b8b96b2d 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -1306,6 +1306,7 @@ static void svc_tcp_init(struct svc_sock *svsk, struct svc_serv *serv)
 	svc_xprt_init(sock_net(svsk->sk_sock->sk), &svc_tcp_class,
 		      &svsk->sk_xprt, serv);
 	set_bit(XPT_CACHE_AUTH, &svsk->sk_xprt.xpt_flags);
+	set_bit(XPT_CONG_CTRL, &svsk->sk_xprt.xpt_flags);
 	if (sk->sk_state == TCP_LISTEN) {
 		dprintk("setting up TCP socket for listening\n");
 		set_bit(XPT_LISTENER, &svsk->sk_xprt.xpt_flags);
diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
index ab2fd5377f94..9d9e4e16080f 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_transport.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
@@ -569,6 +569,14 @@ static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv,
 	spin_lock_init(&cma_xprt->sc_ctxt_lock);
 	spin_lock_init(&cma_xprt->sc_map_lock);
 
+	/*
+	 * Note that this implies that the underlying transport support
+	 * has some form of congestion control (see RFC 7530 section 3.1
+	 * paragraph 2). For now, we assume that all supported RDMA
+	 * transports are suitable here.
+	 */
+	set_bit(XPT_CONG_CTRL, &cma_xprt->sc_xprt.xpt_flags);
+
 	if (listener)
 		set_bit(XPT_LISTENER, &cma_xprt->sc_xprt.xpt_flags);