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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 83CB6C43382 for ; Fri, 28 Sep 2018 12:03:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1E27C2170E for ; Fri, 28 Sep 2018 12:03:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1E27C2170E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=iogearbox.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728123AbeI1S1B (ORCPT ); Fri, 28 Sep 2018 14:27:01 -0400 Received: from www62.your-server.de ([213.133.104.62]:39031 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726024AbeI1S1A (ORCPT ); Fri, 28 Sep 2018 14:27:00 -0400 Received: from [78.46.172.2] (helo=sslproxy05.your-server.de) by www62.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.85_2) (envelope-from ) id 1g5rUZ-0001EL-DM; Fri, 28 Sep 2018 14:03:31 +0200 Received: from [178.197.248.15] (helo=linux.home) by sslproxy05.your-server.de with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1g5rUZ-00011b-82; Fri, 28 Sep 2018 14:03:31 +0200 Subject: Re: [PATCH v3 bpf-next 03/10] bpf: introduce per-cpu cgroup local storage To: Alexei Starovoitov , Roman Gushchin Cc: netdev@vger.kernel.org, Song Liu , linux-kernel@vger.kernel.org, kernel-team@fb.com, Alexei Starovoitov References: <20180926113326.29069-1-guro@fb.com> <20180926113326.29069-4-guro@fb.com> <20180928084528.i5txkac34pmqvs3p@ast-mbp.dhcp.thefacebook.com> <20180928100302.GB9018@castle.DHCP.thefacebook.com> <20180928102458.dbia6xnxkijvkld6@ast-mbp.dhcp.thefacebook.com> From: Daniel Borkmann Message-ID: <21a7ecfb-c7cd-d7aa-01d1-4e055e410817@iogearbox.net> Date: Fri, 28 Sep 2018 14:03:29 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <20180928102458.dbia6xnxkijvkld6@ast-mbp.dhcp.thefacebook.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.100.1/24989/Fri Sep 28 10:53:45 2018) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/28/2018 12:25 PM, Alexei Starovoitov wrote: > On Fri, Sep 28, 2018 at 11:03:03AM +0100, Roman Gushchin wrote: >>>> + >>>> + if (unlikely(map_flags & BPF_EXIST)) >>>> + return -EINVAL; >>> >>> that should have been BPF_NOEXIST ? >> >> Yeah, or maybe even better s/&/!= ? >> It's probably better to require BPF_EXIST flag to update a cgroup storage? >> Agree? If so, let me fix this for both shared and per-cpu versions in >> a follow-up patch. > > I think BPF_ANY is technically valid too. > If we were to require strict BPF_EXIST only, we'd need to fix stable too. > I'm fine with both (BPF_EXIST only and BPF_ANY|BPF_EXIST). > Daniel, what do you think? I'm okay with either option, both seem plausible.