From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next] gro: Handle inline VLAN tags Date: Mon, 19 Nov 2012 19:10:02 -0500 (EST) Message-ID: <20121119.191002.1995098917961576324.davem@davemloft.net> References: <1353111414.10798.64.camel@edumazet-glaptop> <1353112324.2743.81.camel@bwh-desktop.uk.solarflarecom.com> <1353114559.10798.66.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: bhutchings@solarflare.com, netdev@vger.kernel.org, linux-net-drivers@solarflare.com, gallatin@myri.com, herbert@gondor.apana.org.au To: eric.dumazet@gmail.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:34798 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753236Ab2KTAKE (ORCPT ); Mon, 19 Nov 2012 19:10:04 -0500 In-Reply-To: <1353114559.10798.66.camel@edumazet-glaptop> Sender: netdev-owner@vger.kernel.org List-ID: From: Eric Dumazet Date: Fri, 16 Nov 2012 17:09:19 -0800 > On Sat, 2012-11-17 at 00:32 +0000, Ben Hutchings wrote: >> On Fri, 2012-11-16 at 16:16 -0800, Eric Dumazet wrote: >> > On Sat, 2012-11-17 at 00:00 +0000, Ben Hutchings wrote: >> > >> > > I'm not sure what you mean by this. Is your point that the >> > > copy-on-write is never needed? It is still possible for pskb_may_pull() >> > > to fail. >> > > >> > >> > A packet sniffer should have a copy of bad frames, even if dropped later >> > in our stacks. >> > >> > GRO layer is not allowed to drop a frame, even if not 'correct'. >> >> What do you think the accelerated hardware does with frames that have a >> truncated VLAN tag? > > The hardware should send us the frame, exactly like when RX checksum is > wrong. I agree with Eric, and therefore will not apply this patch.