From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: Re: [RFC/PATCH 1/1] format-patch: add an option to record base tree info Date: Tue, 23 Feb 2016 15:49:30 -0600 Message-ID: <87bn77hzbp.fsf@x220.int.ebiederm.org> References: <1456109938-8568-1-git-send-email-xiaolong.ye@intel.com> <1456109938-8568-2-git-send-email-xiaolong.ye@intel.com> <20160223014741.GA21025@wfg-t540p.sh.intel.com> <20160223091740.GA3830@wfg-t540p.sh.intel.com> <87d1rnjil4.fsf@x220.int.ebiederm.org> <3FAB2030-8106-4114-99A4-B04A8A0D22FB@zytor.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Junio C Hamano , Fengguang Wu , Xiaolong Ye , git@vger.kernel.org, ying.huang@intel.com, philip.li@intel.com, julie.du@intel.com, Linus Torvalds , Christoph Hellwig , Dan Carpenter , LKML To: "H. Peter Anvin" X-From: linux-kernel-owner@vger.kernel.org Tue Feb 23 23:01:20 2016 Return-path: Envelope-to: glk-linux-kernel-3@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1aYL1D-000683-2f for glk-linux-kernel-3@plane.gmane.org; Tue, 23 Feb 2016 23:01:19 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756126AbcBWWBG (ORCPT ); Tue, 23 Feb 2016 17:01:06 -0500 Received: from out01.mta.xmission.com ([166.70.13.231]:49397 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755851AbcBWWA7 (ORCPT ); Tue, 23 Feb 2016 17:00:59 -0500 Received: from in01.mta.xmission.com ([166.70.13.51]) by out01.mta.xmission.com with esmtps (TLS1.2:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.82) (envelope-from ) id 1aYL0m-00056E-9R; Tue, 23 Feb 2016 15:00:52 -0700 Received: from 67-3-245-179.omah.qwest.net ([67.3.245.179] helo=x220.int.ebiederm.org.xmission.com) by in01.mta.xmission.com with esmtpsa (TLS1.2:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.82) (envelope-from ) id 1aYL0j-0000Zg-Pi; Tue, 23 Feb 2016 15:00:52 -0700 In-Reply-To: <3FAB2030-8106-4114-99A4-B04A8A0D22FB@zytor.com> (H. Peter Anvin's message of "Tue, 23 Feb 2016 12:46:17 -0800") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) X-XM-AID: U2FsdGVkX18pgcUct47AmNYdvNGPuCxuD6P0YTgqwjs= X-SA-Exim-Connect-IP: 67.3.245.179 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on sa03.xmission.com X-Spam-Level: ** X-Spam-Status: No, score=2.0 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,TVD_RCVD_IP,T_TM2_M_HEADER_IN_MSG,T_TooManySym_01, XMNoVowels,XMSubLong autolearn=disabled version=3.4.0 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.7 XMSubLong Long Subject * 1.5 XMNoVowels Alpha-numberic number with no vowels * 0.0 TVD_RCVD_IP Message was received from an IP address * 0.0 T_TM2_M_HEADER_IN_MSG BODY: No description available. * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa03 1397; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: XMission; sa03 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: **;"H. Peter Anvin" X-Spam-Relay-Country: X-Spam-Timing: total 2009 ms - load_scoreonly_sql: 0.05 (0.0%), signal_user_changed: 3.7 (0.2%), b_tie_ro: 2.7 (0.1%), parse: 1.42 (0.1%), extract_message_metadata: 38 (1.9%), get_uri_detail_list: 7 (0.3%), tests_pri_-1000: 8 (0.4%), tests_pri_-950: 1.96 (0.1%), tests_pri_-900: 1.67 (0.1%), tests_pri_-400: 51 (2.5%), check_bayes: 49 (2.4%), b_tokenize: 20 (1.0%), b_tok_get_all: 13 (0.7%), b_comp_prob: 7 (0.3%), b_tok_touch_all: 3.3 (0.2%), b_finish: 0.81 (0.0%), tests_pri_0: 900 (44.8%), check_dkim_signature: 0.92 (0.0%), check_dkim_adsp: 5 (0.3%), tests_pri_500: 997 (49.7%), poll_dns_idle: 982 (48.9%), rewrite_mail: 0.00 (0.0%) X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Wed, 24 Sep 2014 11:00:52 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Archived-At: "H. Peter Anvin" writes: > On February 23, 2016 12:35:12 PM PST, Junio C Hamano wrote: >>ebiederm@xmission.com (Eric W. Biederman) writes: >> >>> Junio C Hamano writes: >>> >>>> It is valuable for a testing organization to say "We tested this >>>> series on top of version X. We know it works, we have tested on a >>>> lot more hardware than the original developer had, we know this is >>>> good to go." It is a valuable service. >>>> >>>> But that is valuable only if version X is still relevant, isn't it? >>>> >>>> Is the relevance of a version something that is decided by a >>>> developer who submits a patch series, or is it more of an attribute >>>> of the project and where the current integration is happening? >>>> Judging from the responses from Dan to this thread, I think the >>>> answer is the latter, and for the purpose of identifying the >>>> relevant version(s), the project does not even care about the exact >>>> commit, but it wants to know more about which branch the series is >>>> targetted to. >>>> >>>> With that understanding, I find it hard to believe that it buys the >>>> project much for the "base" commit to be recorded in a patch series >>>> and automated testing is done by applying the patches to that exact >>>> commit, which possibly is no-longer-relevant, even though it may >>>> help shielding the testing machinery from "you tested with a wrong >>>> version" complaints. >>>> >>>> Isn't it more valuable for the test robot to say "this may or may >>>> not have worked well with whatever old version the patch series was >>>> based on, but it no longer is useful to the current tip of the >>>> 'master'"? If you consider what benefit the project would gain by >>>> having such a robot, that is the conclusion I have to draw. >>>> >>>> So I still am not convinced that this "record base commit" is a >>>> useful thing to do. >>> >>> So I don't know what value this has to the git project. >> >>Oh, don't worry, I wasn't talking about value this may have to the >>Git project at all. "The value to the project" I mentioned in my >>response was all about the value to the kernel project. >> >>> The value of Fengguag's automated testing to the kernel project is to >>> smoke out really stupid things. >> >>I'll snip your bullet points, but as I wrote, I do understand the >>value of prescreening test. >> >>What I was questioning was what value it gives to that testing to >>use "the developer based this patch on this exact commit" added to >>each incoming patch, and have Fengguag's testing machinery test a >>patch with a base version that may no longer be relevant in the >>context of the project. Compared to that, wouldn't "this no longer >>applies to the branch the series targets" or "this still applies >>cleanly, but no longer compiles because the surrounding API has >>changed" be much more valuable? >> >>In your other message, you mentioned the "index $old..$new" lines, >>and it is possible to use them to find a tree that the patch cleanly >>applies to, but it will not uniquely identify _the_ version the >>patch submitter used. IMHO, finding such _a_ tree from the recent >>history of the branch that the patch targets and testing the patch >>on top of that tree (as opposed to testing the patch in the exact >>context the developer worked on) would give the project a better >>value. > > Personally, as a maintainer, I would love to see the tree ID and > ideally also the commit ID a series is based on. The commit ID is in > some ways less useful since it is non-recreatable (and therefore will > never match for anything but the first patch of a series), but could > be useful to the maintainer. > > As far as putting in a bunch of metainformation that has to be > manually or semimanually obtained, there are a lot of issues with > that, as it way too easily turns into wrong information or potential > information leaks that might make corporate contributors > uncomfortable. I would really love to hear from Fengguag about where this is a practical problem, but I expect the flock of x86 topic tress is probably one of those cases where there are problems for automation to figure out which tree a patch applies to in practice. The mailing list for x86 patches is linux-kernel. Even if you filter by x86@kernel.org to detect it is an x86 patch which topic branch a patch goes to was not clear to me from a quick skim of recent lkml x86 patches. So I could really respect a patch header line that said: tree abcdef0123456789...0123456789abcdef Where the numbers where the truncated tree hash before and after a patch was applied. That would seem to give a little bit of extra sanity checking in the application of git diffs as well. Eric