From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joseph Gasparakis Subject: Re: [PATCH] net-gre-gro: Fix a bug that breaks the forwarding path Date: Thu, 6 Mar 2014 08:42:32 -0800 (PST) Message-ID: References: <1393536377-32243-1-git-send-email-hkchu@google.com> <20140228.165614.1112789771887381245.davem@davemloft.net> <5315FBAA.3030809@mellanox.com> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: Tom Herbert , Joseph Gasparakis , Jerry Chu , David Miller , Pravin B Shelar , Eric Dumazet , Linux Netdev List , Or Gerlitz To: Or Gerlitz Return-path: Received: from mga02.intel.com ([134.134.136.20]:55847 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751052AbaCFQY1 (ORCPT ); Thu, 6 Mar 2014 11:24:27 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Wed, 5 Mar 2014, Or Gerlitz wrote: > On Wed, Mar 5, 2014 at 2:50 AM, Tom Herbert wrote: > > I am concerned that we are overloading the skb->encpasulation > > Guys, so to sum up yesterday's messages on this thread -- do folks > think we can come up with better/proper definition for the > skb->encapsulation bit, or we have to make this multiple bits, or we > have (hopefully not too non linear) dependancy on proper > definitions/usage of the skb->ip_summed field? > > > Or. > >>From my perspective I do not see a gap with the mentioned fields, but I am open if anyone has something to suggest. Joseph > > for instance if this is set in TX path meaning inner headers are valid, > > this should also be true of RX. It might be better if this field > > indicated characteristics of the packet independent of being in RX or > > TX path. For checksum, maybe we should have a separate encap_checksum > > field. Also, to be future proof may this should be two bits for the > > devices that can verify checksums in multiple levels of encapsulations > > (yes, I know this sounds absurd, but it's no more absurd than devices > > vendors taking it upon themselves to parse to some restricted set of > > encapsulations instead of just giving us the full packet checksum! :-)). > > > I hope to have patches soon on fixing CHECKSUM_COMPLETE, I think it > > entails some more state in skb indicating offset and extent of > > checksum value in the packet. An like a said, we need to get out of > > the habit of stashing pseudo csums there (unless CHECKSUM_PARTIAL is > > set). > > > >> Also for Tx, skb->encapsulation should be the indication to the > >> driver that it can use the inner headers (i.e. they are valid) in the skb > >> in order to offload the inner csum. >