From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 463B1904 for ; Wed, 19 Sep 2018 06:16:32 +0000 (UTC) Received: from mail-ua1-f67.google.com (mail-ua1-f67.google.com [209.85.222.67]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 9A57AB0 for ; Wed, 19 Sep 2018 06:16:31 +0000 (UTC) Received: by mail-ua1-f67.google.com with SMTP id f4-v6so2122699uao.10 for ; Tue, 18 Sep 2018 23:16:31 -0700 (PDT) MIME-Version: 1.0 References: <1536142432.8121.6.camel@HansenPartnership.com> <20180905113715.GJ9781@sirena.org.uk> <20180905150315.GA10819@linux.vnet.ibm.com> <20180905115008.22e3d21f@gandalf.local.home> <20180905162007.GO4225@linux.vnet.ibm.com> <1536165914.3627.17.camel@HansenPartnership.com> <1536176428.3627.28.camel@HansenPartnership.com> In-Reply-To: From: Geert Uytterhoeven Date: Wed, 19 Sep 2018 08:16:17 +0200 Message-ID: To: Takashi Iwai Content-Type: text/plain; charset="UTF-8" Cc: James Bottomley , ksummit-discuss@lists.linuxfoundation.org Subject: Re: [Ksummit-discuss] [MAINTAINER SUMMIT] Distribution kernel bugzillas considered harmful List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Iwai-san, On Tue, Sep 18, 2018 at 10:37 PM Takashi Iwai wrote: > On Tue, 18 Sep 2018 15:43:08 +0200, > Martin K. Petersen wrote: > > Sorry I'm a little late to the game here. Been out on vacation. > > > > > We order patches in our trees in the same git-topological-ordering as they > > > are upstream. It has a lot of benefits, most importantly: it doesn't > > > introduce artificial conflicts that don't exist in reality. > > > > > > In order to achieve that, we of course need 1:1 mapping between our > > > patches and upstream commits. Rebases destroy that mapping. > > > > > > And in some areas (scsi is one, but not the only one), we basically had no > > > other choice than considering maintainer's tree to be already "upstream > > > enough", without waiting for Linus' tree merge. > > > > When I discussed this with Johannes a little while ago, I suggested you > > guys used git patch-id to track patches instead of commit ids. That's > > how we track patches applied across many different trees internally. > > Works much better than using the upstream sha. > > What is git patch id? Is there any internal patch tag? It's the output of "git patch-id", which is a hash of the patch, without including its dependencies. This allows to match identical commits in different branches, and is what "git cherry" and "git rebase" use to detect already applied patches. Example (from v4.18.y): $ git show -s e496c9a4c17d4a97ed8d222f368f3b8ad8133fb9 commit e496c9a4c17d4a97ed8d222f368f3b8ad8133fb9 Author: Robert Munteanu Date: Tue Jun 19 11:20:40 2018 +0300 HID: redragon: fix num lock and caps lock LEDs commit dc9b8e85ed95cbe7e3ad0eabb5b48d617bbc365e upstream. The redragon asura keyboard registers two input devices. The initial commit 85455dd906d5 ("HID: redragon: Fix modifier keys for Redragon Asura Keyboard") considered this an error and prevented one of the devices from registering. However, once this is done the num lock and caps lock leds no longer toggle on and off, although the key functionality is not affected. This commit removes the code that prevents the input device registration and restores the num lock and caps lock LEDs. Fixes: 85455dd906d5 ("HID: redragon: Fix modifier keys for Redragon Asura Keyboard") Signed-off-by: Robert Munteanu Signed-off-by: Jiri Kosina Signed-off-by: Greg Kroah-Hartman $ git show e496c9a4c17d4a97ed8d222f368f3b8ad8133fb9 | git patch-id 9d4546a92b459de7249748c0a38b50c989f13bd1 e496c9a4c17d4a97ed8d222f368f3b8ad8133fb9 $ git show dc9b8e85ed95cbe7e3ad0eabb5b48d617bbc365e | git patch-id 9d4546a92b459de7249748c0a38b50c989f13bd1 dc9b8e85ed95cbe7e3ad0eabb5b48d617bbc365e So both commits are identical, as they have the same patch ID. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds