diff --git a/iscsi-scst/README.iser b/iscsi-scst/README.iser
index 819b1b574..19bab9a7a 100644
--- a/iscsi-scst/README.iser
+++ b/iscsi-scst/README.iser
@@ -15,6 +15,14 @@ In order to achieve better performance, it is recommended to specify
 "QueuedCommands 128" parameter per iSER target, since the transport
 is very fast and you usually want to connect it to fast backstorage.
 
+Limitations:
+-------------
+* Bidirectional commands are not supported
+* Block size over 512KB is not supported
+* Maximum number of concurent login requests that can be handled is 127.
+  Note that there may be more connections, but only up to 127 login requests
+  can be handled at the same time.
+
 
 Troubleshooting:
 -----------------
diff --git a/iscsi-scst/kernel/isert-scst/iser_rdma.c b/iscsi-scst/kernel/isert-scst/iser_rdma.c
index 3d526149d..95e93332f 100644
--- a/iscsi-scst/kernel/isert-scst/iser_rdma.c
+++ b/iscsi-scst/kernel/isert-scst/iser_rdma.c
@@ -521,6 +521,9 @@ static void isert_handle_wc_error(struct ib_wc *wc)
 	struct isert_wr *wr = _u64_to_ptr(wc->wr_id);
 	struct isert_cmnd *isert_pdu = wr->pdu;
 	struct isert_connection *isert_conn = wr->conn;
+	struct isert_buf *isert_buf = wr->buf;
+	struct isert_device *isert_dev = wr->isert_dev;
+	struct ib_device *ib_dev = isert_dev->ib_dev;
 
 	TRACE_ENTRY();
 
@@ -538,11 +541,22 @@ static void isert_handle_wc_error(struct ib_wc *wc)
 		}
 		break;
 	case ISER_WR_RDMA_READ:
+		if (isert_buf->sg_cnt != 0) {
+			isert_buf->sg_cnt = 0;
+			ib_dma_unmap_sg(ib_dev, isert_buf->sg, isert_buf->sg_cnt,
+				isert_buf->dma_dir);
+		}
 		isert_pdu_err(&isert_pdu->iscsi);
 		break;
 	case ISER_WR_RECV:
 		/* this should be the Flush, no task has been created yet */
+		break;
 	case ISER_WR_RDMA_WRITE:
+		if (isert_buf->sg_cnt != 0) {
+			isert_buf->sg_cnt = 0;
+			ib_dma_unmap_sg(ib_dev, isert_buf->sg, isert_buf->sg_cnt,
+				isert_buf->dma_dir);
+		}
 		/* RDMA-WR and SEND response of a READ task
 		   are sent together, so when receiving RDMA-WR error,
 		   wait until SEND error arrives to complete the task */
@@ -1592,6 +1606,7 @@ void isert_portal_release(struct isert_portal *portal)
 
 	isert_portal_list_remove(portal);
 
+	kfree(portal);
 	module_put(THIS_MODULE);
 }
 
diff --git a/iscsi-scst/kernel/isert-scst/isert.h b/iscsi-scst/kernel/isert-scst/isert.h
index 9570f030c..c083d536d 100644
--- a/iscsi-scst/kernel/isert-scst/isert.h
+++ b/iscsi-scst/kernel/isert-scst/isert.h
@@ -65,7 +65,7 @@
 
 struct iscsi_conn;
 
-#define ISERT_NR_DEVS 64
+#define ISERT_NR_DEVS 128
 
 struct isert_listener_dev {
 	struct device *dev;