From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xin Long Date: Thu, 08 Oct 2020 09:37:17 +0000 Subject: Re: [PATCH net-next 11/15] sctp: add udphdr to overhead when udp_port is set Message-Id: List-Id: References: <7ff312f910ada8893fa4db57d341c628d1122640.1601387231.git.lucien.xin@gmail.com> <202009300218.2AcHEN0L-lkp@intel.com> <20201003040824.GG70998@localhost.localdomain> <20201005190114.GL70998@localhost.localdomain> In-Reply-To: <20201005190114.GL70998@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Marcelo Ricardo Leitner Cc: kernel test robot , network dev , linux-sctp@vger.kernel.org, kbuild-all@lists.01.org, Neil Horman , Michael Tuexen , davem On Tue, Oct 6, 2020 at 3:01 AM Marcelo Ricardo Leitner wrote: > > On Sat, Oct 03, 2020 at 08:24:34PM +0800, Xin Long wrote: > > On Sat, Oct 3, 2020 at 7:23 PM Xin Long wrote: > > > > > > On Sat, Oct 3, 2020 at 4:12 PM Xin Long wrote: > > > > > > > > On Sat, Oct 3, 2020 at 12:08 PM Marcelo Ricardo Leitner > > > > wrote: > > > > > > > > > > On Wed, Sep 30, 2020 at 03:00:42AM +0800, kernel test robot wrote: > > > > > > Hi Xin, > > > > > > > > > > > > Thank you for the patch! Yet something to improve: > > > > > > > > > > I wonder how are you planning to fix this. It is quite entangled. > > > > > This is not performance critical. Maybe the cleanest way out is to > > > > > move it to a .c file. > > > > > > > > > > Adding a > > > > > #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE) > > > > > in there doesn't seem good. > > > > > > > > > > > In file included from include/net/sctp/checksum.h:27, > > > > > > from net/netfilter/nf_nat_proto.c:16: > > > > > > include/net/sctp/sctp.h: In function 'sctp_mtu_payload': > > > > > > >> include/net/sctp/sctp.h:583:31: error: 'struct net' has no member named 'sctp'; did you mean 'ct'? > > > > > > 583 | if (sock_net(&sp->inet.sk)->sctp.udp_port) > > > > > > | ^~~~ > > > > > > | ct > > > > > > > > > > Here is actually another problem, I'm still thinking how to fix it. > > > > > > > > Now sctp_mtu_payload() returns different value depending on > > > > net->sctp.udp_port. but net->sctp.udp_port can be changed by > > > > "sysctl -w" anytime. so: > > Good point. > > > > > > > > > In sctp_packet_config() it gets overhead/headroom by calling > > > > sctp_mtu_payload(). When 'udp_port' is 0, it's IP+MAC header > > > > size. Then if 'udp_port' is changed to 9899 by 'sysctl -w', > > > > udphdr will also be added to the packet in sctp_v4_xmit(), > > > > and later the headroom may not be enough for IP+MAC headers. > > > > > > > > I'm thinking to add sctp_sock->udp_port, and it'll be set when > > > > the sock is created with net->udp_port. but not sure if we should > > > > update sctp_sock->udp_port with net->udp_port when sending packets? > > I don't think so, > > > > something like: > ... > > diff --git a/net/sctp/output.c b/net/sctp/output.c > > index 6614c9fdc51e..c96b13ec72f4 100644 > > --- a/net/sctp/output.c > > +++ b/net/sctp/output.c > > @@ -91,6 +91,14 @@ void sctp_packet_config(struct sctp_packet *packet, > > __u32 vtag, > > if (asoc) { > > sk = asoc->base.sk; > > sp = sctp_sk(sk); > > + > > + if (unlikely(sp->udp_port != sock_net(sk)->sctp.udp_port)) { > > RFC6951 has: > > 6.1. Get or Set the Remote UDP Encapsulation Port Number > (SCTP_REMOTE_UDP_ENCAPS_PORT) > ... > sue_assoc_id: This parameter is ignored for one-to-one style > sockets. For one-to-many style sockets, the application may fill > in an association identifier or SCTP_FUTURE_ASSOC for this query. > It is an error to use SCTP_{CURRENT|ALL}_ASSOC in sue_assoc_id. > > sue_address: This specifies which address is of interest. If a > wildcard address is provided, it applies only to future paths. > > So I'm not seeing a reason to have a system wide knob that takes > effect in run time like this. > Enable, start apps, and they keep behaving as initially configured. > Need to disable? Restart the apps/sockets. > > Thoughts? Right, not to update it on tx path makes more sense. Thanks. > > > + __u16 port = sock_net(sk)->sctp.udp_port; > > + > > + if (!sp->udp_port || !port) > > + sctp_assoc_update_frag_point(asoc); > > + sp->udp_port = port; > > + } > > } 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=-6.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 9EF38C433E7 for ; Thu, 8 Oct 2020 09:37:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E94A21531 for ; Thu, 8 Oct 2020 09:37:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Zdl5hRdg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728945AbgJHJha (ORCPT ); Thu, 8 Oct 2020 05:37:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39872 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726019AbgJHJha (ORCPT ); Thu, 8 Oct 2020 05:37:30 -0400 Received: from mail-wm1-x342.google.com (mail-wm1-x342.google.com [IPv6:2a00:1450:4864:20::342]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49470C061755; Thu, 8 Oct 2020 02:37:30 -0700 (PDT) Received: by mail-wm1-x342.google.com with SMTP id v12so5809269wmh.3; Thu, 08 Oct 2020 02:37:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=WfZJ4f2PED/NL55ktLAB5sz7CinG8dyvq/2/COAICyY=; b=Zdl5hRdgNQKZY1PSYNQ8pK8SFtKE7VNZcrlPUTpH8T9Q/xeIBDe6B/uWlbniJISByc 6AwwDeg2fdhhl4A1KzoSCI5no87P446Ky8TcxNad8j1VnZinYKAG2pZa7i5g+E08bbtq UW8qoFuRhgFBnjxAoos9XZJUbBX5uZ1zeaddIPV1AkSu4musL+ZIC9UEjVMhBy+BycgE kfBXl2I+byaE494f6bUdZ7rBNBSGQNptUFcl03L7d4N6WjmpLRWfJvlqeFE9pSGEkeSh UHeyZFGINg71bM8I1fCQITyCcgdTduh23hvRFXfx8+/f9uATGrnVT5xicGfLt94kHASB PjjA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=WfZJ4f2PED/NL55ktLAB5sz7CinG8dyvq/2/COAICyY=; b=fqc0sMch240EWAdd3cGFg7zLMfFnQkPUNJBpska1T10xAvWzJXnpe8tepq77OsJYCM LasUcFSHXcrSD5zK8YwiC13ZMs10yaFP2FejkDUy56nauuLc2R2mVKWqGUst+A5EcVHl sfA/r95UyevflPDP2h9IaF8VJ++y7RRk/qSQADntCe+kRJVFP8k4oY46MZRHFWuvAkxr oL1JjECKo85dx0cEEuZD+gn/37qceOEd9YQzuUhJt23hURgU5YhE9bYFtg5ZeV7GMO5A 3VQWxX248LXkxuUtreRLqSjgxIQ7XulYWk1Zm3tr9DxCYieWPG3meiRjXw72UsaASMfc L8hg== X-Gm-Message-State: AOAM5318vbQBI4eIrutJ7DdsRb0shGzQeAUvGN3M1x2N/nVIO6EIkLhB kCGtux4bDY3/FkT4/E0Mhs1YgBd5Xv0H6R1q4cc= X-Google-Smtp-Source: ABdhPJzFcy4mK6bJmMYFxpaZyEo+yPhpxPHh2sNMK6umqOwlFd4WvO6vWoHyEep6TDB1Fj18G+a0Drf/3sYFkbR28vc= X-Received: by 2002:a1c:81ce:: with SMTP id c197mr7670840wmd.111.1602149848958; Thu, 08 Oct 2020 02:37:28 -0700 (PDT) MIME-Version: 1.0 References: <7ff312f910ada8893fa4db57d341c628d1122640.1601387231.git.lucien.xin@gmail.com> <202009300218.2AcHEN0L-lkp@intel.com> <20201003040824.GG70998@localhost.localdomain> <20201005190114.GL70998@localhost.localdomain> In-Reply-To: <20201005190114.GL70998@localhost.localdomain> From: Xin Long Date: Thu, 8 Oct 2020 17:37:17 +0800 Message-ID: Subject: Re: [PATCH net-next 11/15] sctp: add udphdr to overhead when udp_port is set To: Marcelo Ricardo Leitner Cc: kernel test robot , network dev , linux-sctp@vger.kernel.org, kbuild-all@lists.01.org, Neil Horman , Michael Tuexen , davem Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-sctp@vger.kernel.org Message-ID: <20201008093717.eM1cQZbanD5DzAKKpeKr3hsQERlZ4KEFOFMfP7j4HFM@z> On Tue, Oct 6, 2020 at 3:01 AM Marcelo Ricardo Leitner wrote: > > On Sat, Oct 03, 2020 at 08:24:34PM +0800, Xin Long wrote: > > On Sat, Oct 3, 2020 at 7:23 PM Xin Long wrote: > > > > > > On Sat, Oct 3, 2020 at 4:12 PM Xin Long wrote: > > > > > > > > On Sat, Oct 3, 2020 at 12:08 PM Marcelo Ricardo Leitner > > > > wrote: > > > > > > > > > > On Wed, Sep 30, 2020 at 03:00:42AM +0800, kernel test robot wrote: > > > > > > Hi Xin, > > > > > > > > > > > > Thank you for the patch! Yet something to improve: > > > > > > > > > > I wonder how are you planning to fix this. It is quite entangled. > > > > > This is not performance critical. Maybe the cleanest way out is to > > > > > move it to a .c file. > > > > > > > > > > Adding a > > > > > #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE) > > > > > in there doesn't seem good. > > > > > > > > > > > In file included from include/net/sctp/checksum.h:27, > > > > > > from net/netfilter/nf_nat_proto.c:16: > > > > > > include/net/sctp/sctp.h: In function 'sctp_mtu_payload': > > > > > > >> include/net/sctp/sctp.h:583:31: error: 'struct net' has no member named 'sctp'; did you mean 'ct'? > > > > > > 583 | if (sock_net(&sp->inet.sk)->sctp.udp_port) > > > > > > | ^~~~ > > > > > > | ct > > > > > > > > > > Here is actually another problem, I'm still thinking how to fix it. > > > > > > > > Now sctp_mtu_payload() returns different value depending on > > > > net->sctp.udp_port. but net->sctp.udp_port can be changed by > > > > "sysctl -w" anytime. so: > > Good point. > > > > > > > > > In sctp_packet_config() it gets overhead/headroom by calling > > > > sctp_mtu_payload(). When 'udp_port' is 0, it's IP+MAC header > > > > size. Then if 'udp_port' is changed to 9899 by 'sysctl -w', > > > > udphdr will also be added to the packet in sctp_v4_xmit(), > > > > and later the headroom may not be enough for IP+MAC headers. > > > > > > > > I'm thinking to add sctp_sock->udp_port, and it'll be set when > > > > the sock is created with net->udp_port. but not sure if we should > > > > update sctp_sock->udp_port with net->udp_port when sending packets? > > I don't think so, > > > > something like: > ... > > diff --git a/net/sctp/output.c b/net/sctp/output.c > > index 6614c9fdc51e..c96b13ec72f4 100644 > > --- a/net/sctp/output.c > > +++ b/net/sctp/output.c > > @@ -91,6 +91,14 @@ void sctp_packet_config(struct sctp_packet *packet, > > __u32 vtag, > > if (asoc) { > > sk = asoc->base.sk; > > sp = sctp_sk(sk); > > + > > + if (unlikely(sp->udp_port != sock_net(sk)->sctp.udp_port)) { > > RFC6951 has: > > 6.1. Get or Set the Remote UDP Encapsulation Port Number > (SCTP_REMOTE_UDP_ENCAPS_PORT) > ... > sue_assoc_id: This parameter is ignored for one-to-one style > sockets. For one-to-many style sockets, the application may fill > in an association identifier or SCTP_FUTURE_ASSOC for this query. > It is an error to use SCTP_{CURRENT|ALL}_ASSOC in sue_assoc_id. > > sue_address: This specifies which address is of interest. If a > wildcard address is provided, it applies only to future paths. > > So I'm not seeing a reason to have a system wide knob that takes > effect in run time like this. > Enable, start apps, and they keep behaving as initially configured. > Need to disable? Restart the apps/sockets. > > Thoughts? Right, not to update it on tx path makes more sense. Thanks. > > > + __u16 port = sock_net(sk)->sctp.udp_port; > > + > > + if (!sp->udp_port || !port) > > + sctp_assoc_update_frag_point(asoc); > > + sp->udp_port = port; > > + } > > }