From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Lamparter Subject: Re: e100 + VLANs? Date: Mon, 10 Oct 2011 17:28:45 +0200 Message-ID: <20111010152845.GC3260852@jupiter.n2.diac24.net> References: <4E90212D.8030009@msgid.tls.msk.ru> <1318091046.5276.22.camel@edumazet-laptop> <4E9097C0.2030307@gmail.com> <20111010101954.GB2840382@jupiter.n2.diac24.net> <4E9307CB.4050704@msgid.tls.msk.ru> <1318259152.3227.0.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> <20111010151343.GB3260852@jupiter.n2.diac24.net> <1318260235.3227.5.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: David Lamparter , Michael Tokarev , jeffrey.t.kirsher@intel.com, netdev To: Eric Dumazet Return-path: Received: from spaceboyz.net ([87.106.131.203]:36559 "EHLO spaceboyz.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751880Ab1JJP2x (ORCPT ); Mon, 10 Oct 2011 11:28:53 -0400 Content-Disposition: inline In-Reply-To: <1318260235.3227.5.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, Oct 10, 2011 at 05:23:55PM +0200, Eric Dumazet wrote: > Le lundi 10 octobre 2011 =C3=A0 17:13 +0200, David Lamparter a =C3=A9= crit : > > On Mon, Oct 10, 2011 at 05:05:52PM +0200, Eric Dumazet wrote: > > > > When pinging this NIC from another machine over VLAN5, I see > > > > ARP packets coming to it, gets recognized and replies going > > > > back, all on vlan 5. But on the other side, replies comes > > > > WITHOUT a VLAN tag! > > > >=20 > > > > From this NIC's point of view, capturing on whole ethX: > > > >=20 > > > > 00:1f:c6:ef:e5:1b > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100= ), length 60: vlan 5, p 0, ethertype ARP, Ethernet (len 6), IPv4 (len 4= ), Request who-has 10.48.11.2 tell 10.48.11.1, length 42 > > > > 00:90:27:30:6d:1c > 00:1f:c6:ef:e5:1b, ethertype 802.1Q (0x8100= ), length 46: vlan 5, p 0, ethertype ARP, Ethernet (len 6), IPv4 (len 4= ), Reply 10.48.11.2 is-at 00:90:27:30:6d:1c, length 28 > > > >=20 > > > > From the partner point of view, also on whole ethX: > > > >=20 > > > > 00:1f:c6:ef:e5:1b > ff:ff:ff:ff:ff:ff, ethertype 802.1Q (0x8100= ), length 46: vlan 5, p 0, ethertype ARP, Ethernet (len 6), IPv4 (len 4= ), Request who-has 10.48.11.2 tell 10.48.11.1, length 28 > > > > 00:90:27:30:6d:1c > 00:1f:c6:ef:e5:1b, ethertype ARP (0x0806), = length 60: Ethernet (len 6), IPv4 (len 4), Reply 10.48.11.2 is-at 00:90= :27:30:6d:1c, length 46 > > > >=20 > > > > So, the tag gets eaten somewhere along the way... ;) > >=20 > > Hmm. Looks like broken VLAN TX offload, but the driver doesn't even > > implement VLAN offload. Maybe it's broken in its non-implementation= =2E.. > >=20 > > Your "partner" is a known-good setup and can be assumed to be worki= ng > > correctly? This is over a crossover cable, no evil switches involve= d? > >=20 > > > > And I can't really recreate the situation which I had - I know > > > > some packets were flowing, so at least ARP worked. Now it > > > > does not work anymore. > > >=20 > > > What the 'partner' setup looks like ? > > >=20 > > > ip link > > > ip addr > > > ip ro > >=20 > > 'local' setup too please :) >=20 > But here, the remote cleary sends an answer without VLAN tag ;) Huh? The remote sends the ARP request to ff:f..f:ff, which has a VLAN tag in both dumps - but the packet sent from the e100 only has a tag in its own tcpdump... so it might pretty much wind up on the wire without = a tag due to some TX bug... -David