diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c
index 79a3203eccd9901f44338f152301ecb0a0e24577..be416d6850f004642845b65dfdfbf55482ead24c 100644
--- a/drivers/ntb/ntb_transport.c
+++ b/drivers/ntb/ntb_transport.c
@@ -507,17 +507,37 @@ static void ntb_transport_setup_qp_mw(struct ntb_transport *nt,
 	qp->tx_pkts = 0;
 }
 
+static void ntb_free_mw(struct ntb_transport *nt, int num_mw)
+{
+	struct ntb_transport_mw *mw = &nt->mw[num_mw];
+	struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
+
+	if (!mw->virt_addr)
+		return;
+
+	dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr);
+	mw->virt_addr = NULL;
+}
+
 static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size)
 {
 	struct ntb_transport_mw *mw = &nt->mw[num_mw];
 	struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
 
+	/* No need to re-setup */
+	if (mw->size == ALIGN(size, 4096))
+		return 0;
+
+	if (mw->size != 0)
+		ntb_free_mw(nt, num_mw);
+
 	/* Alloc memory for receiving data.  Must be 4k aligned */
 	mw->size = ALIGN(size, 4096);
 
 	mw->virt_addr = dma_alloc_coherent(&pdev->dev, mw->size, &mw->dma_addr,
 					   GFP_KERNEL);
 	if (!mw->virt_addr) {
+		mw->size = 0;
 		dev_err(&pdev->dev, "Unable to allocate MW buffer of size %d\n",
 		       (int) mw->size);
 		return -ENOMEM;
@@ -529,18 +549,6 @@ static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size)
 	return 0;
 }
 
-static void ntb_free_mw(struct ntb_transport *nt, int num_mw)
-{
-	struct ntb_transport_mw *mw = &nt->mw[num_mw];
-	struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
-
-	if (!mw->virt_addr)
-		return;
-
-	dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr);
-	mw->virt_addr = NULL;
-}
-
 static void ntb_qp_link_cleanup(struct work_struct *work)
 {
 	struct ntb_transport_qp *qp = container_of(work,