From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jamal Hadi Salim Subject: Re: [PATCH v3 net-next 2/2] tc: add 'needs_l2' flag to ingress qdisc Date: Mon, 13 Apr 2015 10:28:56 -0400 Message-ID: <552BD2A8.10105@mojatatu.com> References: <1428535575-7736-1-git-send-email-ast@plumgrid.com> <1428535575-7736-2-git-send-email-ast@plumgrid.com> <20150408.224404.1913719826015357860.davem@davemloft.net> <5525EC69.1080606@plumgrid.com> <5526593E.4040608@mojatatu.com> <5526B0E0.7060000@plumgrid.com> <5527C6AE.6010301@mojatatu.com> <55285038.3060806@plumgrid.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: daniel@iogearbox.net, tgraf@suug.ch, jiri@resnulli.us, netdev@vger.kernel.org To: Alexei Starovoitov , David Miller Return-path: Received: from mail-ig0-f178.google.com ([209.85.213.178]:36168 "EHLO mail-ig0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753974AbbDMO26 (ORCPT ); Mon, 13 Apr 2015 10:28:58 -0400 Received: by igblo3 with SMTP id lo3so46993316igb.1 for ; Mon, 13 Apr 2015 07:28:57 -0700 (PDT) In-Reply-To: <55285038.3060806@plumgrid.com> Sender: netdev-owner@vger.kernel.org List-ID: On 04/10/15 18:35, Alexei Starovoitov wrote: >> To your "bugs" comments: >> - updating csum; earlier i said i was conflicted it being a >> useful "feature". >> You are repeating again that it is a bug. It is not. >> This action is intended to mirror or redirect packets, period. > > without updating skb->csum act_mirred is breaking csum for > checksum_complete devices. Ok, could this then be checked for in dev features flags and only then recomputed? > True. The program authors may want to know whether the packet is seen > on ingress or egress and take different actions inside the program, > but forcing them to _always_ parse the packet differently because of > it is not acceptable. Yes, I see your point here as reasonable dilema. But you could add an API call the user always make that resets and unsets the header? It would be a single branch failure for egress/stack source. cheers, jamal