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From: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Subject: Re: Checksum offload queries
Date: Sat, 12 Dec 2015 11:41:37 -0500
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Cc: Edward Cree <ecree@solarflare.com>,
	Linux Kernel Network Developers <netdev@vger.kernel.org>,
	David Miller <davem@davemloft.net>
To: Tom Herbert <tom@herbertland.com>
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On (12/11/15 15:50), Tom Herbert wrote:
> layers of encapsulation. For example, suppose send a UDP packet in
> VXLAN in VXLAN, where packet looks like:
> IP|UDP|VXLAN|Eth|IP|UDP|VXLAN|Eth|IP|UDP. I believe the kernel can set

Without detracting from the fact that you have probably found a bug
for checksumming here..

if you have multiple encapsulations above (vxlan over vxlan?)
I think lot of other things like pmtu may also be broken?  (Each
encaps layer lowers the actual application mtu till the thing starts 
to get absurd)

--Sowmini