set_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
                ipoib_warn(priv, "enabling connected mode "
                           "will cause multicast packet drops\n");
+
+               dev->features &= ~(NETIF_F_IP_CSUM | NETIF_F_SG);
+               priv->tx_wr.send_flags &= ~IB_SEND_IP_CSUM;
+
                ipoib_flush_paths(dev);
                return count;
        }
                clear_bit(IPOIB_FLAG_ADMIN_CM, &priv->flags);
                dev->mtu = min(priv->mcast_mtu, dev->mtu);
                ipoib_flush_paths(dev);
+
+               if (test_bit(IPOIB_FLAG_CSUM, &priv->flags))
+                       dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG;
+
                return count;
        }
 
 
        skb->dev = dev;
        /* XXX get correct PACKET_ type here */
        skb->pkt_type = PACKET_HOST;
+
+       if (test_bit(IPOIB_FLAG_CSUM, &priv->flags) && likely(wc->csum_ok))
+               skb->ip_summed = CHECKSUM_UNNECESSARY;
+
        netif_receive_skb(skb);
 
 repost:
                return;
        }
 
+       if (skb->ip_summed == CHECKSUM_PARTIAL)
+               priv->tx_wr.send_flags |= IB_SEND_IP_CSUM;
+       else
+               priv->tx_wr.send_flags &= ~IB_SEND_IP_CSUM;
+
        if (unlikely(post_send(priv, priv->tx_head & (ipoib_sendq_size - 1),
                               address->ah, qpn,
                               tx_req->mapping, skb_headlen(skb),
 
                                         struct ib_device *hca, u8 port)
 {
        struct ipoib_dev_priv *priv;
+       struct ib_device_attr *device_attr;
        int result = -ENOMEM;
 
        priv = ipoib_intf_alloc(format);
                goto device_init_failed;
        }
 
+       device_attr = kmalloc(sizeof *device_attr, GFP_KERNEL);
+       if (!device_attr) {
+               printk(KERN_WARNING "%s: allocation of %zu bytes failed\n",
+                      hca->name, sizeof *device_attr);
+               goto device_init_failed;
+       }
+
+       result = ib_query_device(hca, device_attr);
+       if (result) {
+               printk(KERN_WARNING "%s: ib_query_device failed (ret = %d)\n",
+                      hca->name, result);
+               kfree(device_attr);
+               goto device_init_failed;
+       }
+
+       if (device_attr->device_cap_flags & IB_DEVICE_UD_IP_CSUM) {
+               set_bit(IPOIB_FLAG_CSUM, &priv->flags);
+               priv->dev->features |= NETIF_F_SG | NETIF_F_IP_CSUM;
+       }
+
+       kfree(device_attr);
+
        /*
         * Set the full membership bit, so that we join the right
         * broadcast group, etc.
        } else
                memcpy(priv->dev->dev_addr + 4, priv->local_gid.raw, sizeof (union ib_gid));
 
-
        result = ipoib_dev_init(priv->dev, hca, port);
        if (result < 0) {
                printk(KERN_WARNING "%s: failed to initialize port %d (ret = %d)\n",