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Re: [Xen-devel] tcp/udp checksum and bridging

> I have a setup with a Linux PV DomU which is on the same bridge as a
> Windows DomU using the PV drivers which Andy and I have been developing.

Cool.  Glad to hear you're progressing well.

> When a tcp packet originates from anywhere but on the same bridge,
> everything is fine, but when the packet originates from a machine on the
> same bridge, the checksum is wrong.
> I think the problem is that the Linux DomU assumes that something else
> will do the checksum of the tcp packet, which is mostly correct unless
> the packet is only bridged and not routed...
> Any suggestions?

I believe the NETTXF_data_validated or NETTXF_csum_blank flags should be set 
in the rx structure's flags in order to indicate that checksum has not been 
done... Are you checking for this?

I'm not really very familiar with this code, this is just something I had a 
vague recollection of existing and was therefore able to dredge up in the 
code.  It's got a lot more complicated than I remember!


Dave: Just a question. What use is a unicyle with no seat?  And no pedals!
Mark: To answer a question with a question: What use is a skateboard?
Dave: Skateboards have wheels.
Mark: My wheel has a wheel!

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