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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next 3/3] geneve: Remote Checksum Offload support
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From: Tom Herbert <tom@herbertland.com>
Date: Tue, 8 Dec 2015 16:11:56 -0800

> I thought about a TLV implementation but there is no base support in
> the kernel for it. It would be great if you could implement the TLV
> loop. Honestly, though, I'm still very leery of the processing
> overhead associated with TLVs in the critical data path. In the
> worst case of RCO we would need to fish for the RCO option though
> the TLV list in both the GRO and normal path for each packet. If the
> TLV lists are long then performance may be negatively affected
> mitigating the value of RCO (needs to be measured).

Open ended TLVs are to me likened to an attack vector waiting to
happen, for the reasons Tom listed.