From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Pirko Subject: Re: [PATCH v2 net] net: Always untag vlan-tagged traffic on input. Date: Mon, 29 Sep 2014 15:05:43 +0200 Message-ID: <20140929130543.GB1839@nanopsycho.orion> References: <1407523333-31455-1-git-send-email-vyasevic@redhat.com> <54295449.7030203@6wind.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Vladislav Yasevich , netdev@vger.kernel.org, Patrick McHardy , Nithin Nayak Sujir , Michael Chan To: Nicolas Dichtel Return-path: Received: from mail-wg0-f46.google.com ([74.125.82.46]:41199 "EHLO mail-wg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751601AbaI2NFr (ORCPT ); Mon, 29 Sep 2014 09:05:47 -0400 Received: by mail-wg0-f46.google.com with SMTP id k14so2909930wgh.29 for ; Mon, 29 Sep 2014 06:05:45 -0700 (PDT) Content-Disposition: inline In-Reply-To: <54295449.7030203@6wind.com> Sender: netdev-owner@vger.kernel.org List-ID: Mon, Sep 29, 2014 at 02:44:57PM CEST, nicolas.dichtel@6wind.com wrote: >Le 08/08/2014 20:42, Vladislav Yasevich a =E9crit : >[snip] >> >>The patch attempt to fix this another way. It moves the vlan header >>stipping code out of the vlan module and always builds it into the >>kernel network core. This way, even if vlan is not supported on >>a virtualizatoin host, the virtual machines running on top of such >>host will still work with VLANs enabled. >After this patch (0d5501c1c828 ("net: Always untag vlan-tagged traffic= on >input.")), tcpdump will not be able to display the VLAN header on inpu= t path. >Is this really intended? I assume you are talking about the case when CONFIG_VLAN_8021Q is "n" right? Because if it is "m" of "y" I see no change in the code. In case of CONFIG_VLAN_8021Q is "n" the only change is that for non-accelerated path, skb->vlan_tci is set and vlan header is stripped. This makes the path same to accelerated path. tcpdump should be able to cope with skb->vlan_tci > > >Regards, >Nicolas