From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?ISO-8859-1?Q?Nicolas_de_Peslo=FCan?=
	<nicolas.2p.debian@gmail.com>
Subject: Re: [PATCH 1/3] vlan: Do not support clearing VLAN_FLAG_REORDER_HDR
Date: Mon, 23 May 2011 21:48:12 +0200
Message-ID: <4DDAB9FC.8050207@gmail.com>
References: <m17h9jp7js.fsf@fess.ebiederm.org> <BANLkTi=4JJa-J-p_JbY1PfooT75KfSB4uA@mail.gmail.com> <m1ei3qjzix.fsf_-_@fess.ebiederm.org> <4DD97A44.2020708@candelatech.com> <m1wrhigy37.fsf@fess.ebiederm.org> <BANLkTinXFYzzj3R97mKH-90xM64BDwN8aA@mail.gmail.com> <BANLkTik6etR8V1qeDnYBKt6BaODBe8kUOw@mail.gmail.com> <m1ei3qdwa6.fsf@fess.ebiederm.org> <BANLkTi=BN6Aza7eU=D+WqJgVsVuswT5PDg@mail.gmail.com> <m139k57nzx.fsf@fess.ebiederm.org> <20110523104339.GA2769@psychotron>
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Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
	Changli Gao <xiaosuo@gmail.com>,
	Ben Greear <greearb@candelatech.com>,
	David Miller <davem@davemloft.net>, netdev@vger.kernel.org,
	shemminger@linux-foundation.org, kaber@trash.net, fubar@us.ibm.com,
	eric.dumazet@gmail.com, andy@greyhouse.net,
	Jesse Gross <jesse@nicira.com>
To: Jiri Pirko <jpirko@redhat.com>
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Le 23/05/2011 12:43, Jiri Pirko a =E9crit :
> Mon, May 23, 2011 at 11:41:22AM CEST, ebiederm@xmission.com wrote:
>> Changli Gao<xiaosuo@gmail.com>  writes:
>>
>>> On Mon, May 23, 2011 at 9:45 AM, Eric W. Biederman
>>> <ebiederm@xmission.com>  wrote:
>>>>> In another side, is there a specification which defines the
>>>>> hw-accel-vlan-rx?
>>>>
>>>> I don't know.
>>>>
>>>> I have just been trying to clean up the mess since some of the
>>>> hw-accel-vlan code broke my use case, by delivering packets with
>>>> priority but no vlan (aka vlan 0 packets) twice to my pf_packet so=
ckets.
>>>>
>>>
>>> OK. But if we have decided to simulate the hw-accel-vlan-rx, I thin=
k
>>> we'd better adjust the place where we put the emulation code. The v=
ery
>>> beginnings of netif_rx() and neif_receive_skb() are better. Then rp=
s
>>> can support vlan packets without any change.
>>
>> That sounds nice. Patches are welcome.
>>
>> In principle it should be doable with some code motion.  I don't thi=
nk
>> moving vlan_untag earlier constitutes a bug fix.
>
> I do not think that is doable. Consider multi tagged packets. The pla=
ce
> just after "another_round" takes care about that.
>
> Btw what's the rationale to move untag to earlier position?

Maybe simply because we try to mimic hw-accel, and hw-accel untagging d=
efinitely happens before we=20
enter __netif_receive_skb and only happens once.

So having software untagging inside the __netif_receive_skb loop looks =
different.

	Nicolas.