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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 7036FC433E0 for ; Tue, 30 Jun 2020 21:17:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3C23A20656 for ; Tue, 30 Jun 2020 21:17:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="BMWsT4ae" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729447AbgF3VRs (ORCPT ); Tue, 30 Jun 2020 17:17:48 -0400 Received: from mail.efficios.com ([167.114.26.124]:48592 "EHLO mail.efficios.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725805AbgF3VRs (ORCPT ); Tue, 30 Jun 2020 17:17:48 -0400 Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id 125932C72E3; Tue, 30 Jun 2020 17:17:47 -0400 (EDT) Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id dX8LJcERVS4j; Tue, 30 Jun 2020 17:17:46 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.efficios.com (Postfix) with ESMTP id B14522C7393; Tue, 30 Jun 2020 17:17:46 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.efficios.com B14522C7393 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=efficios.com; s=default; t=1593551866; bh=dzOtmJ7mD/siyGoPxQC/+AbiDTyc52D1unXi3sYhHw4=; h=Date:From:To:Message-ID:MIME-Version; b=BMWsT4ae0NFCJ7Ar9Wj/SDYypbB4SF4CqanRW+dwWOnP+GK8ukFotA8/0X3ZNkB/T 1V95PFBjmkA5EYmVmvP3OKlTGV7mLADFG4gJ62Nm2NV4PQCGiBWaRktNCvUmZlckwu r7ZWl5ZhfWVO8a3kcgf9YovcOjsHZ/HYtGUAxThOmKOvsnsmtBlN5hz8RRoNR3zdEv MolT2QWCjHCKHUoyJkeBtPOXhn2r+G4/sT+OaxU3KE9i4psxZ02NjnPLQuBJST3H5f jIU1V9zvvQyWxBuezPLl8Tv38IGeQlrelEw8V7iNEUrUu2Vwtjs9kTtUP8j00T3SMb tuMOsYxVkRlEw== X-Virus-Scanned: amavisd-new at efficios.com Received: from mail.efficios.com ([127.0.0.1]) by localhost (mail03.efficios.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id RjPVrSqWHdX1; Tue, 30 Jun 2020 17:17:46 -0400 (EDT) Received: from mail03.efficios.com (mail03.efficios.com [167.114.26.124]) by mail.efficios.com (Postfix) with ESMTP id 9DE582C71DC; Tue, 30 Jun 2020 17:17:46 -0400 (EDT) Date: Tue, 30 Jun 2020 17:17:46 -0400 (EDT) From: Mathieu Desnoyers To: Eric Dumazet Cc: "David S. Miller" , Linus Torvalds , linux-kernel , netdev , Yuchung Cheng , Jonathan Rajotte-Julien Message-ID: <474095696.17969.1593551866537.JavaMail.zimbra@efficios.com> In-Reply-To: References: <312079189.17903.1593549293094.JavaMail.zimbra@efficios.com> <20200630.134429.1590957032456466647.davem@davemloft.net> Subject: Re: [regression] TCP_MD5SIG on established sockets MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [167.114.26.124] X-Mailer: Zimbra 8.8.15_GA_3945 (ZimbraWebClient - FF77 (Linux)/8.8.15_GA_3928) Thread-Topic: TCP_MD5SIG on established sockets Thread-Index: bT5tgAuCnz/dlB46lWW2qWJ3mIXuLQ== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- 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! Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com