From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jakub Kicinski <jakub.kicinski@netronome.com>
Subject: Re: [RFC bpf-next 2/6] net: xdp: RX meta data infrastructure
Date: Fri, 6 Jul 2018 18:20:47 -0700
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To: Alexei Starovoitov <alexei.starovoitov@gmail.com>
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On Fri, 6 Jul 2018 18:00:13 -0700, Alexei Starovoitov wrote:
> On Fri, Jul 06, 2018 at 05:40:43PM -0700, Jakub Kicinski wrote:
> > 
> > Could we just say that at the start we expose only existing SKB fields
> > (csum, hash, mark) and the meaning of the is the same as in the SKB?  
> 
> what would be the meaning of 'hash' ? Over which fields?
> Does it support inner and outer packets? How about udp encap (vxlan and friends) ?

We don't seem to need to answer that for the rest of the stack, no?  We
can expose the "hash type" field as well if that's *really* necessary.

> Same question of csum... tcp only? 

Shouldn't we just stick to CHECKSUM_COMPLETE?

> how about crc for sctp?

That's harder to answer.  Can cls_bpf access such info?

> What is 'mark' ?

Same thing it would be on an skb.  Most likely set with an offloaded TC
rule?