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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 04A6EC433F5 for ; Mon, 7 Mar 2022 10:23:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235278AbiCGKXs (ORCPT ); Mon, 7 Mar 2022 05:23:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44410 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242198AbiCGKVm (ORCPT ); Mon, 7 Mar 2022 05:21:42 -0500 Received: from mail-ej1-x633.google.com (mail-ej1-x633.google.com [IPv6:2a00:1450:4864:20::633]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B48891ADF for ; Mon, 7 Mar 2022 01:59:03 -0800 (PST) Received: by mail-ej1-x633.google.com with SMTP id a8so30624595ejc.8 for ; Mon, 07 Mar 2022 01:59:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bgdev-pl.20210112.gappssmtp.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=rAWZGHckQWG83FD6qmD6twtYogiaFbCPHvkaTYgvtrc=; b=OuN6Fob8ZXARHAUb6lnubhL4AxmCZJ99baH8LErGQIlvfbE5eL1uatf1DTdBRtKv9P MoAAKYrvhoHS0rTcHVQ+C2+C9tubmu3xnQYptbsKli159zmbJHX/23gJS/iXyW9nXAfB Poa3z7zMsdiDz8R1IqpEWHHEj23m3Ntksg1QHLPBM2UKPWfE2q2Oyu7sK1Sz9UIky6dk /yhTHzTvwJydUatAF4uJBeZbELpjFZa961DWbw/0gqxCYiQDVtcZR9c/QQD0IkkseYWM RzRc699Un2EYGq27FOp5ywEaDZlsWOWjwEt3WDwENMvcZaLw4cEeHrigtbp8kneuqzfH xAOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=rAWZGHckQWG83FD6qmD6twtYogiaFbCPHvkaTYgvtrc=; b=7SWPRhl3jAM0fR0viNVyr980uqG5nC728XJanXL3OO87OL7ye2yWjnfciyk01vUtqj jaE5jD/X0EM7Q1rEdiRC/sSmKQvbpHkGXb+zCbqRcDuLnC+ORM0uFE7mBrjSMDmc1qtj Z1sQdaea4WOnNGeMl4tyfGSEsG28bNkkxXsMCcv3Z4glRjmQ0WAyjV5OBITj7DYfu0mB eZc+/jdv9ihitD48at6YQxNZv23OAmKbAxPTRi14KADp16hjEh46l99PQr6nXL6DPUul mYOskIpP1tHwB7ERWcxaFWH6pz1PTexxB5fiWW3bcVBkwlLmoe6ORX7tikq67Bqq3O4A 2C/Q== X-Gm-Message-State: AOAM533VS/yyCF1VtD1t+z/HNMcOdZN1IoUbEbHbbm/LP6X8C6cBDM3D Dw68TsKnUFt4aLs61tUGmhpqhIO6y6Xp/gN4MUW4mQ== X-Google-Smtp-Source: ABdhPJyFIGlx6PfBNJwwECfjPB46G0LNPkPrBmFv66KUSM4TH0xQBhxXMM2hyhDHPkU331BJW8BrmsFxGfgNtYbBGdM= X-Received: by 2002:a17:907:728b:b0:6da:97db:b66d with SMTP id dt11-20020a170907728b00b006da97dbb66dmr8327290ejc.636.1646647141819; Mon, 07 Mar 2022 01:59:01 -0800 (PST) MIME-Version: 1.0 References: <20211217153555.9413-1-marcelo.jimenez@gmail.com> In-Reply-To: From: Bartosz Golaszewski Date: Mon, 7 Mar 2022 10:58:51 +0100 Message-ID: Subject: Re: [PATCH] gpio: Revert regression in sysfs-gpio (gpiolib.c) To: Thorsten Leemhuis Cc: Linus Walleij , Marcelo Roberto Jimenez , stable , regressions@lists.linux.dev, "open list:GPIO SUBSYSTEM" , Thierry Reding , Vidya Sagar , Geert Uytterhoeven , Stephen Rothwell , Edmond Chung , Andrew Chant , Will McVicker , Sergio Tanzilli Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Fri, Mar 4, 2022 at 8:13 AM Thorsten Leemhuis wrote: > > Hi, this is your Linux kernel regression tracker. > > On 16.02.22 15:40, Bartosz Golaszewski wrote: > > On Tue, Feb 15, 2022 at 10:56 PM Linus Walleij wrote: > >> > >> On Mon, Feb 14, 2022 at 12:24 AM Marcelo Roberto Jimenez > >> wrote: > >>> On Sat, Feb 12, 2022 at 1:55 PM Linus Walleij wrote: > >> > >>>> I am curious about the usecases and how deeply you have built > >>>> yourselves into this. > >>> > >>> I don't know if I understand what you mean, sorry. > >> > >> Why does the user need the sysfs ABI? What is it used for? > >> > >> I.e what is the actual use case? > >> > >>>>> In any case, the upstream file should be enough to test the issue reported here. > >>>> > >>>> The thing is that upstream isn't super happy that you have been > >>>> making yourselves dependent on features that we are actively > >>>> discouraging and then demanding that we support these features. > >>> > >>> Hum, demanding seems to be a strong word for what I am doing here. > >>> > >>> Deprecated should not mean broken. My point is: the API seems to be > >>> currently broken. User space apps got broken, that's a fact. I even > >>> took the time to bisect the kernel and show you which commit broke it. > >>> So, no, I am not demanding. More like reporting and providing a > >>> temporary solution to those with a similar problem. > >>> > >>> Maybe it is time to remove the API, but this is up to "upstream". > >>> Leaving the API broken seems pointless and unproductive. > >>> > >>> Sorry for the "not super happiness of upstream", but maybe upstream > >>> got me wrong. > >>> > >>> We are not "making ourselves dependent on features ...". The API was > >>> there. We used it. Now it is deprecated, ok, we should move on. I got > >>> the message. > >> > >> Ouch I deserved some slamming for this. > >> > >> I'm sorry if I came across as harsh :( > >> > >> I just don't know how to properly push for this. > >> > >> I have even pushed the option of the deprecated sysfs ABI > >> behind the CONFIG_EXPERT option, which should mean that > >> the kernel config has been made by someone who has checked > >> the option "yes I am an expert I know what I am doing" > >> yet failed to observe that this ABI is obsoleted since 5 years > >> and hence failed to be an expert. > >> > >> Of course the ABI (not API really) needs to be fixed if we can find the > >> problem. It's frustrating that fixing it seems to fix broken other > >> features which are not deprecated, hence the annoyance on my > >> part. > >> > > > > I'm afraid we'll earn ourselves a good old LinusRant if we keep > > pushing the character device as a solution to the problem here. > > Marcelo is right after all: he used an existing user interface, the > > interface broke, it must be fixed. > > > > I would prefer to find a solution that fixes Marcelo's issue while > > keeping the offending patches in tree but it seems like the issue is > > more complicated and will require some rework of the sysfs interface. > > > > In which case unless there are objections I lean towards reverting the > > relevant commits. > > Sounds good to me, but that was two weeks ago and afaics nothing > happened since then. Or did the discussion continue somewhere else? > Now queued for fixes, thanks for the reminder. Bart > >>> And I will also tell the dev team that they must use the GPIO char dev > >>> and libgpiod from now on and must port everything to it. And we will > >>> likely have another group of people who are not super happy, but > >>> that's life... :) > >> > >> I'm happy to hear this! > > Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) > > P.S.: As the Linux kernel's regression tracker I'm getting a lot of > reports on my table. I can only look briefly into most of them and lack > knowledge about most of the areas they concern. I thus unfortunately > will sometimes get things wrong or miss something important. I hope > that's not the case here; if you think it is, don't hesitate to tell me > in a public reply, it's in everyone's interest to set the public record > straight. > > #regzbot poke