From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3A71C433DF for ; Wed, 1 Jul 2020 06:02:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D3F7C2074D for ; Wed, 1 Jul 2020 06:02:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726953AbgGAGCI (ORCPT ); Wed, 1 Jul 2020 02:02:08 -0400 Received: from m9784.mail.qiye.163.com ([220.181.97.84]:45005 "EHLO m9784.mail.qiye.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726779AbgGAGCI (ORCPT ); Wed, 1 Jul 2020 02:02:08 -0400 Received: from [192.168.188.14] (unknown [106.75.220.2]) by m9784.mail.qiye.163.com (Hmail) with ESMTPA id D593141611; Wed, 1 Jul 2020 14:02:04 +0800 (CST) Subject: Re: [PATCH net] net/sched: act_mirred: fix fragment the packet after defrag in act_ct To: Cong Wang Cc: Paul Blakey , Linux Kernel Network Developers References: <1593485646-14989-1-git-send-email-wenxu@ucloud.cn> <10af044d-c51b-9b85-04b9-ea97a3c3ebdb@ucloud.cn> From: wenxu Message-ID: <8b06ac17-e19b-90f3-6dd2-0274a0ee474b@ucloud.cn> Date: Wed, 1 Jul 2020 14:02:02 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US X-HM-Spam-Status: e1kfGhgUHx5ZQUtXWQgYFAkeWUFZVkpVSk5PS0tLSk1IS0xDSEpZV1koWU FJQjdXWS1ZQUlXWQ8JGhUIEh9ZQVkXIjULOBw*Ix8ILxgxDQMeSiswSTocVlZVSE9MKElZV1kJDh ceCFlBWTU0KTY6NyQpLjc#WVdZFhoPEhUdFFlBWTQwWQY+ X-HM-Sender-Digest: e1kMHhlZQR0aFwgeV1kSHx4VD1lBWUc6PhQ6Mio4QzgwSiw1PikUOiIp KT1PFDpVSlVKTkJITkNISElOS0lOVTMWGhIXVQweFQMOOw4YFxQOH1UYFUVZV1kSC1lBWUpLTVVM TlVJSUtVSVlXWQgBWUFJQ01KNwY+ X-HM-Tid: 0a7308f7cf222086kuqyd593141611 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 7/1/2020 1:52 PM, Cong Wang wrote: > On Tue, Jun 30, 2020 at 7:36 PM wenxu wrote: >> >> On 7/1/2020 3:02 AM, Cong Wang wrote: >>> On Mon, Jun 29, 2020 at 7:55 PM wrote: >>>> From: wenxu >>>> >>>> The fragment packets do defrag in act_ct module. The reassembled packet >>>> over the mtu in the act_mirred. This big packet should be fragmented >>>> to send out. >>> This is too brief. Why act_mirred should handle the burden introduced by >>> act_ct? And why is this 158-line change targeting -net not -net-next? >> Hi Cong, >> >> In the act_ct the fragment packets will defrag to a big packet and do conntrack things. >> >> But in the latter filter mirred action, the big packet normally send over the mtu of outgoing device. >> >> So in the act_mirred send the packet should fragment. > Why act_mirred? Not, for a quick example, a new action called act_defrag? > I understand you happen to use the combination of act_ct and act_mirred, > but that is not the reason we should make act_mirred specifically work > for your case. Only forward packet case need do fragment again and there is no need do defrag explicit.