Re: [Xen-devel] [PATCH] Network Checksum Removal

[Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>]

On 25 May 2005, at 22:35, Jon Mason wrote:

> The problem with the bridge device is that all traffic generated in 
> dom0 will
> be software checksummed, regardless of whether it needs to be or not.  
> In
> Xen's case, it will software checksum all traffic to domU, even though 
> the
> vif device is advertising NETIF_F_NO_CSUM.
>
> This is because the stack doesn't see the features of the children 
> devices of
> the bridge, only the features of the bridge device itself.  I created 
> a quick
> hack to work around this, and started the discussion on the Linux 
> netdev
> mailing list about how to fix the problem.  From this discussion, a 
> patch was
> created which does most of what we want, but needs to be slightly 
> modified to
> be optimal for Xen.  I will post the Xen optimized patch as soon as I 
> have it
> done.
But we no longer bring up an IP interface on the bridge device -- we 
use veth0 instead, which advertises NETIF_F_IP_CSUM.
 -- Keir


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel