From mboxrd@z Thu Jan  1 00:00:00 1970
From: Edward Cree <ecree@solarflare.com>
Subject: Re: [net PATCH v2 2/2] ipv4/GRO: Make GRO conform to RFC 6864
Date: Wed, 6 Apr 2016 16:55:47 +0100
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Cc: Tom Herbert <tom@herbertland.com>,
	David Miller <davem@davemloft.net>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	Alexander Duyck <alexander.duyck@gmail.com>,
	Alex Duyck <aduyck@mirantis.com>,
	Jesse Gross <jesse@kernel.org>,
	Eric Dumazet <edumazet@google.com>,
	Linux Kernel Network Developers <netdev@vger.kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On 06/04/16 16:39, Eric Dumazet wrote:
> Look at the mess of some helpers in net/core/skbuff.c, and imagine the
> super mess it would be if using a concept of 'super packet with various
> headers on each segment'.
Maybe I'm still not explaining this very well, but there is _no_ concept of
'super packet [anything]' in this idea.  There is just 'list of skbs that
were all received in the same NAPI poll, and have not yet been determined to
be different'.

Any layer that doesn't want to deal with this stuff will always have the
option of "while (skb = skb_dequeue(list)) my_normal_receive_function(skb);"
and in fact I'd make that happen by default for anything that hadn't
registered a function to take a list.
> netfilter is already complex, it would become a nightmare.
A netfilter hook could, for instance, run on each packet in the list, then
partition the list into sub-lists of packets that all had the same verdict
(letting go of any that were DROP or STOLEN).  That doesn't seem like it
should be nightmarish.

-Ed