Netfront's use of nh.raw and h.raw for storing page+offset is a bit
hinky, and it breaks with upcoming network stack updates which reduce
these fields to sub-pointer sizes.  Fortunately, skb offers the "cb"
field specifically for stashing this kind of info, so use it.

Signed-off-by: Jeremy Fitzhardinge <[EMAIL PROTECTED]>
Cc: Herbert Xu <[EMAIL PROTECTED]>
Cc: Chris Wright <[EMAIL PROTECTED]>
Cc: Christian Limpach <[EMAIL PROTECTED]>

---
 drivers/net/xen-netfront.c |   18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

===================================================================
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -52,6 +52,13 @@
 #include <xen/page.h>
 #include <xen/grant_table.h>
 
+struct netfront_cb {
+       struct page *page;
+       unsigned offset;
+};
+
+#define NETFRONT_SKB_CB(skb)   ((struct netfront_cb *)((skb)->cb))
+
 /*
  * Mutually-exclusive module options to select receive data path:
  *  rx_copy : Packets are copied by network backend into local memory
@@ -944,10 +951,11 @@ static void handle_incoming_queue(struct
        struct sk_buff *skb;
 
        while ((skb = __skb_dequeue(rxq)) != NULL) {
-               struct page *page = (struct page *)skb->nh.raw;
+               struct page *page = NETFRONT_SKB_CB(skb)->page;
                void *vaddr = page_address(page);
-
-               memcpy(skb->data, vaddr + (skb->h.raw - skb->nh.raw),
+               unsigned offset = NETFRONT_SKB_CB(skb)->offset;
+
+               memcpy(skb->data, vaddr + offset,
                       skb_headlen(skb));
 
                if (page != skb_shinfo(skb)->frags[0].page)
@@ -1251,8 +1259,8 @@ err:
                        }
                }
 
-               skb->nh.raw = (void *)skb_shinfo(skb)->frags[0].page;
-               skb->h.raw = skb->nh.raw + rx->offset;
+               NETFRONT_SKB_CB(skb)->page = skb_shinfo(skb)->frags[0].page;
+               NETFRONT_SKB_CB(skb)->offset = rx->offset;
 
                len = rx->status;
                if (len > RX_COPY_THRESHOLD)

-- 

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