diff --git a/net/sunrpc/xprtrdma/fmr_ops.c b/net/sunrpc/xprtrdma/fmr_ops.c
index d5f95bb39300..629e53973321 100644
--- a/net/sunrpc/xprtrdma/fmr_ops.c
+++ b/net/sunrpc/xprtrdma/fmr_ops.c
@@ -191,7 +191,7 @@ fmr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
 
 	mr = rpcrdma_mr_get(r_xprt);
 	if (!mr)
-		return ERR_PTR(-ENOBUFS);
+		return ERR_PTR(-EAGAIN);
 
 	pageoff = offset_in_page(seg1->mr_offset);
 	seg1->mr_offset -= pageoff;	/* start of page */
diff --git a/net/sunrpc/xprtrdma/frwr_ops.c b/net/sunrpc/xprtrdma/frwr_ops.c
index 90f688f19783..e21781cb20be 100644
--- a/net/sunrpc/xprtrdma/frwr_ops.c
+++ b/net/sunrpc/xprtrdma/frwr_ops.c
@@ -367,7 +367,7 @@ frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
 			rpcrdma_mr_defer_recovery(mr);
 		mr = rpcrdma_mr_get(r_xprt);
 		if (!mr)
-			return ERR_PTR(-ENOBUFS);
+			return ERR_PTR(-EAGAIN);
 	} while (mr->frwr.fr_state != FRWR_IS_INVALID);
 	frwr = &mr->frwr;
 	frwr->fr_state = FRWR_IS_VALID;
diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index 4bc0f4d94a01..e8adad33d0bb 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -365,7 +365,7 @@ rpcrdma_encode_read_list(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,
 		seg = r_xprt->rx_ia.ri_ops->ro_map(r_xprt, seg, nsegs,
 						   false, &mr);
 		if (IS_ERR(seg))
-			return PTR_ERR(seg);
+			goto out_maperr;
 		rpcrdma_mr_push(mr, &req->rl_registered);
 
 		if (encode_read_segment(xdr, mr, pos) < 0)
@@ -377,6 +377,11 @@ rpcrdma_encode_read_list(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,
 	} while (nsegs);
 
 	return 0;
+
+out_maperr:
+	if (PTR_ERR(seg) == -EAGAIN)
+		xprt_wait_for_buffer_space(rqst->rq_task, NULL);
+	return PTR_ERR(seg);
 }
 
 /* Register and XDR encode the Write list. Supports encoding a list
@@ -423,7 +428,7 @@ rpcrdma_encode_write_list(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,
 		seg = r_xprt->rx_ia.ri_ops->ro_map(r_xprt, seg, nsegs,
 						   true, &mr);
 		if (IS_ERR(seg))
-			return PTR_ERR(seg);
+			goto out_maperr;
 		rpcrdma_mr_push(mr, &req->rl_registered);
 
 		if (encode_rdma_segment(xdr, mr) < 0)
@@ -440,6 +445,11 @@ rpcrdma_encode_write_list(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,
 	*segcount = cpu_to_be32(nchunks);
 
 	return 0;
+
+out_maperr:
+	if (PTR_ERR(seg) == -EAGAIN)
+		xprt_wait_for_buffer_space(rqst->rq_task, NULL);
+	return PTR_ERR(seg);
 }
 
 /* Register and XDR encode the Reply chunk. Supports encoding an array
@@ -481,7 +491,7 @@ rpcrdma_encode_reply_chunk(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,
 		seg = r_xprt->rx_ia.ri_ops->ro_map(r_xprt, seg, nsegs,
 						   true, &mr);
 		if (IS_ERR(seg))
-			return PTR_ERR(seg);
+			goto out_maperr;
 		rpcrdma_mr_push(mr, &req->rl_registered);
 
 		if (encode_rdma_segment(xdr, mr) < 0)
@@ -498,6 +508,11 @@ rpcrdma_encode_reply_chunk(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,
 	*segcount = cpu_to_be32(nchunks);
 
 	return 0;
+
+out_maperr:
+	if (PTR_ERR(seg) == -EAGAIN)
+		xprt_wait_for_buffer_space(rqst->rq_task, NULL);
+	return PTR_ERR(seg);
 }
 
 /**
@@ -724,8 +739,8 @@ rpcrdma_prepare_send_sges(struct rpcrdma_xprt *r_xprt,
  * Returns:
  *	%0 if the RPC was sent successfully,
  *	%-ENOTCONN if the connection was lost,
- *	%-EAGAIN if not enough pages are available for on-demand reply buffer,
- *	%-ENOBUFS if no MRs are available to register chunks,
+ *	%-EAGAIN if the caller should call again with the same arguments,
+ *	%-ENOBUFS if the caller should call again after a delay,
  *	%-EMSGSIZE if the transport header is too small,
  *	%-EIO if a permanent problem occurred while marshaling.
  */
@@ -868,10 +883,7 @@ rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst)
 	return 0;
 
 out_err:
-	if (ret != -ENOBUFS) {
-		pr_err("rpcrdma: header marshaling failed (%d)\n", ret);
-		r_xprt->rx_stats.failed_marshal_count++;
-	}
+	r_xprt->rx_stats.failed_marshal_count++;
 	return ret;
 }
 
diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c
index 47b4604e820a..08196896953d 100644
--- a/net/sunrpc/xprtrdma/transport.c
+++ b/net/sunrpc/xprtrdma/transport.c
@@ -689,7 +689,8 @@ xprt_rdma_free(struct rpc_task *task)
  * Returns:
  *	%0 if the RPC message has been sent
  *	%-ENOTCONN if the caller should reconnect and call again
- *	%-ENOBUFS if the caller should call again later
+ *	%-EAGAIN if the caller should call again
+ *	%-ENOBUFS if the caller should call again after a delay
  *	%-EIO if a permanent error occurred and the request was not
  *		sent. Do not try to send this message again.
  */
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index 520e7e4fe203..d36c18f26cd3 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -1048,8 +1048,9 @@ rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt)
 	list_splice(&all, &buf->rb_all);
 	r_xprt->rx_stats.mrs_allocated += count;
 	spin_unlock(&buf->rb_mrlock);
-
 	trace_xprtrdma_createmrs(r_xprt, count);
+
+	xprt_write_space(&r_xprt->rx_xprt);
 }
 
 static void