From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jarek Poplawski <jarkao2@gmail.com>
Subject: Re: [PATCH net-next-2.6] net: force a fresh timestamp for ingress
	packets
Date: Fri, 17 Dec 2010 08:34:13 +0000
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Cc: David Miller <davem@davemloft.net>,
	Changli Gao <xiaosuo@gmail.com>,
	netdev <netdev@vger.kernel.org>,
	Patrick McHardy <kaber@trash.net>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Fri, Dec 17, 2010 at 09:08:17AM +0100, Eric Dumazet wrote:
> Le vendredi 17 d=E9cembre 2010 ?? 07:30 +0000, Jarek Poplawski a =E9c=
rit :
>=20
> > It is wrong because it brings back the inconsistency with ping etc.
> > described by Alex Sidorenko in the changelog of netem patch, but
> > use normal (not netem) ingress scheduling (ping results shouldn't
> > depend on sniffers).
>=20
> Care to explain why only netem should take care of this delaying
> problem ?
> If a packet is delayed on other qdisc, dont we have the same problem =
?

netem was treated as a special case just to pretend (lie) about the
net outside (still not depending on sniffers), but it's hard to
believe there are "normal" ping users after netem.

>=20
> Right now, ping lies, giving different results if a sniffer is active=
 or
> not.
>=20
> Care to suggest an alternative patch, because I am lost at this point=
 ?

Just what I wrote earlier: consider one additional cloning in
dev_queue_xmit_nit or maybe resetting the timestamp with act_skbedit?

Thanks,
Jarek P.