+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,24)
+ /* Before 2.6.24 these fields were not copied when
+ * doing an skb_copy_expand. */
+ nskb->ip_summed = skb->ip_summed;
+ nskb->csum = skb->csum;
+#endif
+#if defined(CONFIG_XEN) && defined(HAVE_PROTO_DATA_VALID)
+ /* These fields are copied in skb_clone but not in
+ * skb_copy or related functions. We need to manually
+ * copy them over here. */
+ nskb->proto_data_valid = skb->proto_data_valid;
+ nskb->proto_csum_blank = skb->proto_csum_blank;
+#endif