diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index 3f50828802de..1285f04cdac1 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -747,6 +747,7 @@ inline int rpcrdma_prepare_send_sges(struct rpcrdma_xprt *r_xprt,
 				     struct xdr_buf *xdr,
 				     enum rpcrdma_chunktype rtype)
 {
+	struct rpcrdma_sendctx *sc;
 	int ret;
 
 	ret = -EAGAIN;
@@ -789,7 +790,9 @@ inline int rpcrdma_prepare_send_sges(struct rpcrdma_xprt *r_xprt,
 	return 0;
 
 out_unmap:
-	rpcrdma_sendctx_cancel(req->rl_sendctx);
+	sc = req->rl_sendctx;
+	rpcrdma_sendctx_cancel(sc);
+	rpcrdma_sendctx_unget_locked(r_xprt, sc);
 out_nosc:
 	trace_xprtrdma_prepsend_failed(&req->rl_slot, ret);
 	return ret;
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index 8392ba4bcdca..04b286223b24 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -631,6 +631,11 @@ static void rpcrdma_sendctxs_destroy(struct rpcrdma_xprt *r_xprt)
 	/* The QP is drained, but the final unsignaled Sends might not
 	 * have been walked by a signaled Send completion. Release those
 	 * Send owners before request buffers are reset.
+	 *
+	 * Unlike the completion sweep, this walk can visit slots with
+	 * no Send posted: after a partial rpcrdma_sendctxs_create()
+	 * failure on reconnect, rb_sc_head and rb_sc_tail are stale,
+	 * and slots between them can be NULL or have sc_req clear.
 	 */
 	for (i = rpcrdma_sendctx_next(buf, buf->rb_sc_tail);
 	     i != rpcrdma_sendctx_next(buf, buf->rb_sc_head);
@@ -703,6 +708,12 @@ static unsigned long rpcrdma_sendctx_next(struct rpcrdma_buffer *buf,
 	return likely(item < buf->rb_sc_last) ? item + 1 : 0;
 }
 
+static unsigned long rpcrdma_sendctx_prev(struct rpcrdma_buffer *buf,
+					  unsigned long item)
+{
+	return item > 0 ? item - 1 : buf->rb_sc_last;
+}
+
 /**
  * rpcrdma_sendctx_get_locked - Acquire a send context
  * @r_xprt: controlling transport instance
@@ -759,6 +770,29 @@ struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_xprt *r_xprt)
 	return NULL;
 }
 
+/**
+ * rpcrdma_sendctx_unget_locked - Release an unposted send context
+ * @r_xprt: controlling transport instance
+ * @sc: send context to release
+ *
+ * Usage: Called when no Send is posted for the sendctx most
+ * recently returned by rpcrdma_sendctx_get_locked().
+ *
+ * The caller serializes calls to this function and to
+ * rpcrdma_sendctx_get_locked() (per transport).
+ */
+void rpcrdma_sendctx_unget_locked(struct rpcrdma_xprt *r_xprt,
+				  struct rpcrdma_sendctx *sc)
+{
+	struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
+
+	if (WARN_ON_ONCE(buf->rb_sc_ctxs[buf->rb_sc_head] != sc))
+		return;
+
+	buf->rb_sc_head = rpcrdma_sendctx_prev(buf, buf->rb_sc_head);
+	xprt_write_space(&r_xprt->rx_xprt);
+}
+
 /**
  * rpcrdma_sendctx_put_locked - Release a send context
  * @r_xprt: controlling transport instance
@@ -776,8 +810,7 @@ static void rpcrdma_sendctx_put_locked(struct rpcrdma_xprt *r_xprt,
 	unsigned long next_tail;
 
 	/* Release previously completed but unsignaled Sends by walking
-	 * up the queue until @sc is found. Entries left behind by a
-	 * failed rpcrdma_prepare_send_sges() have sc_req cleared.
+	 * up the queue until @sc is found.
 	 */
 	next_tail = buf->rb_sc_tail;
 	do {
@@ -787,8 +820,7 @@ static void rpcrdma_sendctx_put_locked(struct rpcrdma_xprt *r_xprt,
 
 		/* ORDER: item must be accessed _before_ tail is updated */
 		cur = buf->rb_sc_ctxs[next_tail];
-		if (cur->sc_req)
-			rpcrdma_sendctx_unmap(cur);
+		rpcrdma_sendctx_unmap(cur);
 
 	} while (buf->rb_sc_ctxs[next_tail] != sc);
 
diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h
index ae036719f840..4cbc941e4a3e 100644
--- a/net/sunrpc/xprtrdma/xprt_rdma.h
+++ b/net/sunrpc/xprtrdma/xprt_rdma.h
@@ -495,6 +495,8 @@ void rpcrdma_req_destroy(struct rpcrdma_req *req);
 int rpcrdma_buffer_create(struct rpcrdma_xprt *);
 void rpcrdma_buffer_destroy(struct rpcrdma_buffer *);
 struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_xprt *r_xprt);
+void rpcrdma_sendctx_unget_locked(struct rpcrdma_xprt *r_xprt,
+				  struct rpcrdma_sendctx *sc);
 
 struct rpcrdma_mr *rpcrdma_mr_get(struct rpcrdma_xprt *r_xprt);
 void rpcrdma_mrs_refresh(struct rpcrdma_xprt *r_xprt);