Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757620AbXKFTBy (ORCPT ); Tue, 6 Nov 2007 14:01:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756861AbXKFTBh (ORCPT ); Tue, 6 Nov 2007 14:01:37 -0500 Received: from ns2.lanforge.com ([66.165.47.211]:46102 "EHLO ns2.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756639AbXKFTBg (ORCPT ); Tue, 6 Nov 2007 14:01:36 -0500 Message-ID: <4730B8ED.7020301@candelatech.com> Date: Tue, 06 Nov 2007 10:56:45 -0800 From: Ben Greear Organization: Candela Technologies User-Agent: Thunderbird 1.5.0.10 (X11/20070301) MIME-Version: 1.0 To: Krzysztof Halasa CC: Patrick McHardy , David Miller , djohnson+linux-kernel@sw.starentnetworks.com, jes@trained-monkey.org, mchan@broadcom.com, ram.vepa@neterion.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bguo@sw.starentnetworks.com Subject: Re: [PATCH 1/2] NET: Re-add VLAN tag for devices incapable of keeping it References: <472A6089.7020104@hp.com> <18223.22291.622615.129374@zeus.sw.starentnetworks.com> <472F5A33.20906@trash.net> <20071105.151544.175839612.davem@davemloft.net> <472FB375.1020802@trash.net> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1218 Lines: 31 Krzysztof Halasa wrote: > Patrick McHardy writes: > >> I think there is one more case that matters, which is briding >> from a device with VLAN stripping for a VLAN not configured >> locally. The tag will be stripped and will be lost for forwarded >> packets. > > I think we should drop such packets on RX. Anyway we shouldn't > forward them. Bridging eth0 to eth1 should not pay attention to VLAN tags at all (if the pkt comes in on VLAN 7, it should go out on VLAN 7), in my opinion. If the NIC is stripping the VLAN header, then this cannot work unless something re-builds the VLAN header. If the stripped VLAN header is placed into the skb, then any code that does need to rebuild it can do so. It may be less efficient, but users can just not use that NIC hardware for high-end solutions, and at any rate, less efficient is better than broken. Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/