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=-10.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 456E6C4360C for ; Thu, 10 Oct 2019 04:30:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1C5BF208C3 for ; Thu, 10 Oct 2019 04:30:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="bf70iZzy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727552AbfJJEa0 (ORCPT ); Thu, 10 Oct 2019 00:30:26 -0400 Received: from mail-pg1-f196.google.com ([209.85.215.196]:34298 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725829AbfJJEaZ (ORCPT ); Thu, 10 Oct 2019 00:30:25 -0400 Received: by mail-pg1-f196.google.com with SMTP id y35so2833261pgl.1; Wed, 09 Oct 2019 21:30:25 -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=AT1qXEvZ+lQA7q1Z71j11lVp8JI+71RILIKUCFl5DKI=; b=bf70iZzyYJHlRpq3VlAxj/4S5gY1uZNsyF6fU1xHSUCByV+eMZBMvgaCY7OC0WGGI5 xy/2Lg09kPSUy2iEaUpTWfJk38pJTVfUp7n8OkH5axKB0NoWP/khROfd61VTuvF9XBn4 NXwgnGb8EVFJyku92dH2NlmnQgiIA1Ov7pHUVMWO64r258kPf3lAO9EwRRH4k1BIf5V6 Tq4OlS79M6v7lgBpYqNnBfgysdvyTxqFP9yrpwRtOFOSrHTW0bqGyiTSDN2SFKynU660 nhgtimefy+yoxqPiJfNaMFQFV+c73rJAeBnS9DM663vNuus7QCAdW7uQvFq7cxu3SbLa h2MQ== 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=AT1qXEvZ+lQA7q1Z71j11lVp8JI+71RILIKUCFl5DKI=; b=WyY9cL7gcPJiD1F9KsJAJP6WpLEp4VHQfdUwgD45DOnH06sVbwoSHQBAXnkXqe6xFW NaoS+/XVcI8Tlo6nQX2K03iBXg7xFEkQ58jwjmizkGj8+uQAMGpjgdTSiGuLEc1Df+qh fpq432SOpsZLdx6KRELQu+SX2qR9R9srVw8qPNa3I0BnpHbaoidjEALSMiXgZaapqv7M +aKUB8LuAIFUZUyz9sbc88wVK9RKgP/X3Bg3kSZdgW5TSe+S5ClHE3X+hYpAUKhf1g0J h+VjmyWk0+rr/BZGp2aHU/77DqYr9vmHcQWZpOEU5l+Kd2VGDwKSJw2PO4QUXIQVHR3d iqYw== X-Gm-Message-State: APjAAAWEGW2zvzAvq8Vka0VvWhQRtPD9Am7RaaRzL0SiRrTvJ+Tc6Wzy thah3a9TC+V+T8BXgw25/wA= X-Google-Smtp-Source: APXvYqxAGi9RKiZZfYMaYp3blstGL8vkWv2x/vmRLdHFU7Vu+wMMTuEUBcdFzSMOO4Ll9Tn6GCVuMA== X-Received: by 2002:a17:90a:f495:: with SMTP id bx21mr8347624pjb.84.1570681824990; Wed, 09 Oct 2019 21:30:24 -0700 (PDT) Received: from [192.168.86.235] (c-73-241-150-70.hsd1.ca.comcast.net. [73.241.150.70]) by smtp.gmail.com with ESMTPSA id i132sm3404043pgd.47.2019.10.09.21.30.23 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 09 Oct 2019 21:30:24 -0700 (PDT) Subject: Re: [PATCH net] netfilter: conntrack: avoid possible false sharing To: Jakub Kicinski , Eric Dumazet Cc: Pablo Neira Ayuso , Jozsef Kadlecsik , Florian Westphal , netfilter-devel@vger.kernel.org, netdev , Eric Dumazet , syzbot , Jozsef Kadlecsik References: <20191009161913.18600-1-edumazet@google.com> <20191009212451.0522979f@cakuba.netronome.com> From: Eric Dumazet Message-ID: <7b7193d5-c93f-b81a-f4a0-ad63ed8196c3@gmail.com> Date: Wed, 9 Oct 2019 21:30:22 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20191009212451.0522979f@cakuba.netronome.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 10/9/19 9:24 PM, Jakub Kicinski wrote: > On Wed, 9 Oct 2019 09:19:13 -0700, Eric Dumazet wrote: >> As hinted by KCSAN, we need at least one READ_ONCE() >> to prevent a compiler optimization. >> >> More details on : >> https://github.com/google/ktsan/wiki/READ_ONCE-and-WRITE_ONCE#it-may-improve-performance >> >> [...] >> >> Fixes: cc16921351d8 ("netfilter: conntrack: avoid same-timeout update") >> Signed-off-by: Eric Dumazet >> Reported-by: syzbot >> Cc: Pablo Neira Ayuso >> Cc: Jozsef Kadlecsik >> Cc: Florian Westphal > > Applied, thank you. > > Not queuing for stable, please let me know if I should. > This is fine really, thanks.