if (ib_mac_rsp->flags2 & IB_MAC_IOCB_RSP_P) {
                QPRINTK(qdev, RX_STATUS, DEBUG, "Promiscuous Packet.\n");
        }
-       if (ib_mac_rsp->flags1 & (IB_MAC_IOCB_RSP_IE | IB_MAC_IOCB_RSP_TE)) {
-               QPRINTK(qdev, RX_STATUS, ERR,
-                       "Bad checksum for this %s packet.\n",
-                       ((ib_mac_rsp->
-                         flags2 & IB_MAC_IOCB_RSP_T) ? "TCP" : "UDP"));
-               skb->ip_summed = CHECKSUM_NONE;
-       } else if (qdev->rx_csum &&
-                  ((ib_mac_rsp->flags2 & IB_MAC_IOCB_RSP_T) ||
-                   ((ib_mac_rsp->flags2 & IB_MAC_IOCB_RSP_U) &&
-                    !(ib_mac_rsp->flags1 & IB_MAC_IOCB_RSP_NU)))) {
-               QPRINTK(qdev, RX_STATUS, DEBUG, "RX checksum done!\n");
-               skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+
+       skb->protocol = eth_type_trans(skb, ndev);
+       skb->ip_summed = CHECKSUM_NONE;
+
+       /* If rx checksum is on, and there are no
+        * csum or frame errors.
+        */
+       if (qdev->rx_csum &&
+               !(ib_mac_rsp->flags2 & IB_MAC_IOCB_RSP_ERR_MASK) &&
+               !(ib_mac_rsp->flags1 & IB_MAC_CSUM_ERR_MASK)) {
+               /* TCP frame. */
+               if (ib_mac_rsp->flags2 & IB_MAC_IOCB_RSP_T) {
+                       QPRINTK(qdev, RX_STATUS, DEBUG,
+                                       "TCP checksum done!\n");
+                       skb->ip_summed = CHECKSUM_UNNECESSARY;
+               } else if ((ib_mac_rsp->flags2 & IB_MAC_IOCB_RSP_U) &&
+                               (ib_mac_rsp->flags3 & IB_MAC_IOCB_RSP_V4)) {
+               /* Unfragmented ipv4 UDP frame. */
+                       struct iphdr *iph = (struct iphdr *) skb->data;
+                       if (!(iph->frag_off &
+                               cpu_to_be16(IP_MF|IP_OFFSET))) {
+                               skb->ip_summed = CHECKSUM_UNNECESSARY;
+                               QPRINTK(qdev, RX_STATUS, DEBUG,
+                                               "TCP checksum done!\n");
+                       }
+               }
        }
+
        qdev->stats.rx_packets++;
        qdev->stats.rx_bytes += skb->len;
-       skb->protocol = eth_type_trans(skb, ndev);
        skb_record_rx_queue(skb, rx_ring - &qdev->rx_ring[0]);
        if (qdev->vlgrp && (ib_mac_rsp->flags2 & IB_MAC_IOCB_RSP_V)) {
                QPRINTK(qdev, RX_STATUS, DEBUG,