Re: Interdomain/interpartition communication without a checksum

["David S. Miller" <davem@xxxxxxxxxxxxx>]

From: Jon Mason <jdmason@xxxxxxxxxx>
Date: Tue, 17 May 2005 11:34:20 -0500

> --- ../xen-unstable-pristine/linux-2.6.11-xen0/include/linux/skbuff.h 
> 2005-03-02 01:38:38.000000000 -0600
> +++ linux-2.6.11-xen0/include/linux/skbuff.h  2005-05-13 10:43:08.000000000 
> -0500
> @@ -37,6 +37,10 @@
>  #define CHECKSUM_HW 1
>  #define CHECKSUM_UNNECESSARY 2
>  
> +#define SKB_CLONED   1
> +#define SKB_NOHDR    2
> +#define SKB_FDW_NO_CSUM      4
> +


You create SKB_NOHDR yet do not make use of it to
replace skb->nohdr.

> @@ -603,7 +603,7 @@ int pskb_expand_head(struct sk_buff *skb
>       skb->mac.raw += off;
>       skb->h.raw   += off;
>       skb->nh.raw  += off;
> -     skb->cloned   = 0;
> +     skb->flags    &= SKB_CLONED;
>       atomic_set(&skb_shinfo(skb)->dataref, 1);
>       return 0;

This does not clear SKB_CLONED, it makes it the only possible
bit set.  Clearly this was not your intention.