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=-8.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 64910C433E0 for ; Tue, 30 Jun 2020 21:24:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F54520663 for ; Tue, 30 Jun 2020 21:24:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="KDvS/FCw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729517AbgF3VYB (ORCPT ); Tue, 30 Jun 2020 17:24:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32918 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725805AbgF3VX5 (ORCPT ); Tue, 30 Jun 2020 17:23:57 -0400 Received: from mail-yb1-xb2c.google.com (mail-yb1-xb2c.google.com [IPv6:2607:f8b0:4864:20::b2c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11B4FC061755 for ; Tue, 30 Jun 2020 14:23:57 -0700 (PDT) Received: by mail-yb1-xb2c.google.com with SMTP id m16so10822191ybf.4 for ; Tue, 30 Jun 2020 14:23:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=U30OFkrejSXAU09n9FsbqbkjUpt98e9QYxgvQQIe3VE=; b=KDvS/FCwcnss0qNhjm0NpFuNqkT7h3+EZ/xTBejWNC8QggWOPRJWUE8lGjmgzgV4F6 CKf3p9gg6ckn82XV/hd/V6dkDn08v8XcOCSJNKHFSXuHZNiKaGjrHXGn9sSJe5aHXe/Q D63Zq9xMzVygOREvAxd6d6vzeRwiewKn26ZbEYxBhF4Q03S4e1eGmpulMnWYQXIqJash L6mFduHsYhmW8O6cCcAtlc8hH/CUI6t++Qs3AdOOw2bnPAejcIGYeXT3CVGzGOHseQMo igumKYVCtgwRFuysW54R/kDb77jbtnUaDF2s95dLKfDnxwIx9NYnkdJedHJHsAu+jU02 Rhjw== 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=U30OFkrejSXAU09n9FsbqbkjUpt98e9QYxgvQQIe3VE=; b=ir1q7KW3HjBBQI3VKNhq5GYHXWn9V44r/w7ci/aqSoxuKPVL4IfVgucl3UZcfhemnW EMFgZvNex8vZkNtXdQ910Pw2xDLie8zVhikYP2KMHiU8g0Oubpe8SYHTjshv83R/fh3J SezV71FuUuzv8u7EHvXgA/OpikjUfzxCQfrgUDJ7+EL+fJywb17yCCgLuX+74o40IrFI SYQzEblG4zwtcPnfRLNEtCy8z0jBWwuzGj1VDddZHfvhEAnWJja383yqS/6kKaX0nbZg aewxUp+FjjhDB4vidnjRAwKJjr8uy6+onUmBlGqxlJQ/bZo2aKZgtaKsHfLPp9F/5duw 8QcA== X-Gm-Message-State: AOAM5338+ooKh/V7q43fan59tLp9GSoXFcnQiRJaMhhvrSEXKrp+e4W1 OW0JEZr3R2FBEVKqR+V/3ymSTZ3H9DLqjgvcHcPIrQ== X-Google-Smtp-Source: ABdhPJwvRiGn2p72OxM41uEpcwGeHq27tY+8sROq1FeyItQfz0F+5TMDBnzWOnk7yXafVjj9vG5ep+wApKq2Y25+RlU= X-Received: by 2002:a25:ec0d:: with SMTP id j13mr34790409ybh.364.1593552235823; Tue, 30 Jun 2020 14:23:55 -0700 (PDT) MIME-Version: 1.0 References: <312079189.17903.1593549293094.JavaMail.zimbra@efficios.com> <20200630.134429.1590957032456466647.davem@davemloft.net> <474095696.17969.1593551866537.JavaMail.zimbra@efficios.com> In-Reply-To: <474095696.17969.1593551866537.JavaMail.zimbra@efficios.com> From: Eric Dumazet Date: Tue, 30 Jun 2020 14:23:44 -0700 Message-ID: Subject: Re: [regression] TCP_MD5SIG on established sockets To: Mathieu Desnoyers Cc: "David S. Miller" , Linus Torvalds , linux-kernel , netdev , Yuchung Cheng , Jonathan Rajotte-Julien Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 30, 2020 at 2:17 PM Mathieu Desnoyers wrote: > > ----- On Jun 30, 2020, at 4:56 PM, Eric Dumazet edumazet@google.com wrote: > > > On Tue, Jun 30, 2020 at 1:44 PM David Miller wrote: > >> > >> From: Eric Dumazet > >> Date: Tue, 30 Jun 2020 13:39:27 -0700 > >> > >> > The (C) & (B) case are certainly doable. > >> > > >> > A) case is more complex, I have no idea of breakages of various TCP > >> > stacks if a flow got SACK > >> > at some point (in 3WHS) but suddenly becomes Reno. > >> > >> I agree that C and B are the easiest to implement without having to > >> add complicated code to handle various negotiated TCP option > >> scenerios. > >> > >> It does seem to be that some entities do A, or did I misread your > >> behavioral analysis of various implementations Mathieu? > >> > >> Thanks. > > > > Yes, another question about Mathieu cases is do determine the behavior > > of all these stacks vs : > > SACK option > > TCP TS option. > > I will ask my customer's networking team to investigate these behaviors, > which will allow me to prepare a thorough reply to the questions raised > by Eric and David. I expect to have an answer within 2-3 weeks at most. > > Thank you! Great, I am working on adding back support for (B) & (C) by the end of this week.