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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, 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 5A854C43331 for ; Mon, 11 Nov 2019 10:22:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3215D20818 for ; Mon, 11 Nov 2019 10:22:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726804AbfKKKWB (ORCPT ); Mon, 11 Nov 2019 05:22:01 -0500 Received: from www62.your-server.de ([213.133.104.62]:58814 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726768AbfKKKWB (ORCPT ); Mon, 11 Nov 2019 05:22:01 -0500 Received: from sslproxy05.your-server.de ([78.46.172.2]) by www62.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1iU6pS-00069U-UP; Mon, 11 Nov 2019 11:21:51 +0100 Received: from [2a02:1205:507e:bf80:bef8:7f66:49c8:72e5] (helo=pc-11.home) by sslproxy05.your-server.de with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1iU6pS-000BbE-Bq; Mon, 11 Nov 2019 11:21:50 +0100 Subject: Re: [PATCH v3 bpf-next 02/18] bpf: Add bpf_arch_text_poke() helper To: Peter Zijlstra , David Miller Cc: alexei.starovoitov@gmail.com, ast@kernel.org, x86@kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, Kernel-team@fb.com References: <59d3af80-a781-9765-4d01-4c8006cd574f@fb.com> <20191108213624.GM3079@worktop.programming.kicks-ass.net> <20191108.133924.1397692397131607421.davem@davemloft.net> <20191111081403.GM4131@hirez.programming.kicks-ass.net> From: Daniel Borkmann Message-ID: <79170599-e29d-7d65-d7f5-0f22bcd15873@iogearbox.net> Date: Mon, 11 Nov 2019 11:21:49 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20191111081403.GM4131@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.101.4/25629/Sun Nov 10 11:19:04 2019) Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On 11/11/19 9:14 AM, Peter Zijlstra wrote: > On Fri, Nov 08, 2019 at 01:39:24PM -0800, David Miller wrote: >> From: Peter Zijlstra >> Date: Fri, 8 Nov 2019 22:36:24 +0100 >> >>> The cover leter is not preserved and should therefore >> ... >> >> The cover letter is +ALWAYS+ preserved, we put them in the merge >> commit. > > Good to know; is this a netdev special? I've not seen this before. I think it might be netdev special, and given developers are often used to this practice on netdev, we've adopted the same for both bpf trees as well if the cover letter contains a useful high level summary of the whole set. We've recently changed our workflow a bit after last maintainers summit and reuse Thomas' mb2q [0] in our small collection of scripts [1], so aside from other useful features, for every commit under bpf/bpf-next there is now also a 'Link:' tag pointing to https://lore.kernel.org/bpf/ archive, thus cover letter or discussions could alternatively be found this way. One downside of merge commit as cover letter is that they are usually lost (*) once commits get cherry-picked into stable trees or other downstream, backport heavy kernels, so with a 'Link:' tag it's a convenient way to quickly get more context or discussions for those cases. > Is there a convenient git command to find the merge commit for a given > regular commit? Say I've used git-blame to find a troublesome commit, > then how do I find the merge commit for it? Once you have the sha, you could for example retrieve the corresponding merge commit from the upstream tree (as top commit) via: $ git log ..master --ancestry-path --merges --reverse > Also, I still think this does not excuse weak individual Changelogs. Ideally commit messages should be as self-contained as possible to have all the necessary context w/o having to look up other resources also given issue (*) above. Thanks, Daniel [0] https://git.kernel.org/pub/scm/linux/kernel/git/tglx/quilttools.git/ [1] https://git.kernel.org/pub/scm/linux/kernel/git/dborkman/pw.git/