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=-4.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,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 76501C49EA6 for ; Thu, 24 Jun 2021 14:36:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5F2EA613EB for ; Thu, 24 Jun 2021 14:36:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232172AbhFXOif (ORCPT ); Thu, 24 Jun 2021 10:38:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230296AbhFXOie (ORCPT ); Thu, 24 Jun 2021 10:38:34 -0400 Received: from mail-oi1-x236.google.com (mail-oi1-x236.google.com [IPv6:2607:f8b0:4864:20::236]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F005C061574 for ; Thu, 24 Jun 2021 07:36:14 -0700 (PDT) Received: by mail-oi1-x236.google.com with SMTP id h9so7555584oih.4 for ; Thu, 24 Jun 2021 07:36:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=GgunliXPEwff0RKxEiN1J3KRr0eB3DJG3ZFXRas/V3I=; b=Zvx56x6zcZaTgyaRjgdWwZd9al8fjol7n37wvs7PvBzNqqt3NPYe0CqlH8RB+FHdfC YSZMvL6NfiWg5gTC4fmR+g6oLWCdDQc4MFbasqap/gf3Fg8hUauJfcB0LCBk97QsDnVe K4WbbcwhsgO5iIn7K2CKQb9vrbyx4H4EtnNRlVy465Ni1DUd8TbaHfEX7ddIn0sGEoW5 N0KXh3hcpBIYWHt/UbnpP728A6I6hrsCwfzaJWnAflap9SsxOHSZ9xjFbl+S8d0BBpYZ JKgBRH4IHjt4e9XE2l1EyTPbD23orAveucJOUGTC9OnS5Z5KDv08PVirBmGE3IaFPMaT pPHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=GgunliXPEwff0RKxEiN1J3KRr0eB3DJG3ZFXRas/V3I=; b=c6xxPUOhELoXr4rsPJU4MEVN5cxDbni/+V/3/nA5bRV5965MGVXM9IYHGLtDhkjbzZ wRx/D/q0s4JPfv+BoLUfdzyxTvZMJ9jNurhO/yC/88gKEikBlub8s/NAvUPWyy0pZU0U 8KUNo7y1nnxLubSDcUcd3aagPtW0H4Erf8DqUlRmWMfGBDx5fMHp8mRvd8hFPe7rqNCo bUzwFal8Ah7IsFXgugMNEn4qO49nsEbwL4E1+I64dKsdkX+CB056weUzp/imJHNJvzyp NMFS13BFMjA5BC7wpBE0QzUscVSVsEijh6bQfpcjXaZw3hxO+AWibDxSgao1SwJnFgia C0nQ== X-Gm-Message-State: AOAM5336uhsmS9sh0kb165QxyySowWZdLaecVNJ9NAAjXaDoOOyNzTUA I+ZKQP243trACmjYSG64ASw= X-Google-Smtp-Source: ABdhPJxFFZUEtbd9g9REHuLxpHtufZK+FFG+wxNLzeNVYG8fmopCIuARiO57XLpKZHBv+d6e675Nig== X-Received: by 2002:a05:6808:128b:: with SMTP id a11mr1373916oiw.123.1624545373779; Thu, 24 Jun 2021 07:36:13 -0700 (PDT) Received: from Davids-MacBook-Pro.local ([8.48.134.38]) by smtp.googlemail.com with ESMTPSA id o2sm625549oom.26.2021.06.24.07.36.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 24 Jun 2021 07:36:13 -0700 (PDT) Subject: Re: [PATCH net] ip6_tunnel: fix GRE6 segmentation To: Guillaume Nault Cc: Jakub Kicinski , davem@davemloft.net, netdev@vger.kernel.org, yoshfuji@linux-ipv6.org, dsahern@kernel.org, vfedorenko@novek.ru References: <20210622015254.1967716-1-kuba@kernel.org> <33902f8c-e14a-7dc6-9bde-4f8f168505b5@gmail.com> <20210622152451.7847bc24@kicinski-fedora-PC1C0HJN.hsd1.ca.comcast.net> <592a8a33-dfb8-c67f-c9e6-0e1bab37b00d@gmail.com> <20210623091458.40fb59c6@kicinski-fedora-PC1C0HJN.hsd1.ca.comcast.net> <5011b8aa-8bbf-9172-0982-599afed69c5d@gmail.com> <20210624133915.GA4606@pc-32.home> From: David Ahern Message-ID: <18a17215-e4e4-a1ef-b2d0-a934dca2b21c@gmail.com> Date: Thu, 24 Jun 2021 08:36:12 -0600 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210624133915.GA4606@pc-32.home> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 6/24/21 7:39 AM, Guillaume Nault wrote: > On Wed, Jun 23, 2021 at 12:28:05PM -0600, David Ahern wrote: >> On 6/23/21 10:14 AM, Jakub Kicinski wrote: >>> Noob question, why do we need that 2 sec wait with IPv6 sometimes? >>> I've seen it randomly in my local testing as well I wasn't sure if >>> it's a bug or expected. >> >> It is to let IPv6 DAD to complete otherwise the address will not be >> selected as a source address. That typically results in test failures. >> There are sysctl settings that can prevent the race and hence the need >> for the sleep. > > But Jakub's script uses "nodad" in the "ip address add ..." commands. > Isn't that supposed to disable DAD entirely for the new address? > Why would it need an additional "sleep 2"? > it should yes. I think the selftests have acquired a blend of nodad, sysctl and sleep. I'm sure it could be cleaned up and made consistent.