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 AB183C433EF for ; Mon, 10 Jan 2022 14:44:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235694AbiAJOoW (ORCPT ); Mon, 10 Jan 2022 09:44:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37688 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234981AbiAJOoV (ORCPT ); Mon, 10 Jan 2022 09:44:21 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 686A0C06173F for ; Mon, 10 Jan 2022 06:44:21 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E61CC60E33 for ; Mon, 10 Jan 2022 14:44:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4BBB9C36AE3; Mon, 10 Jan 2022 14:44:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1641825860; bh=QTlLtVmA4M6A/doosWcn+xwS48663pzABVMvW6Gyr4M=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=EgfaRDFnEHM8wW0auRDMXieHj6JQR1i6sQ/AQUPzl2To/Di+UjDQCQx1SaNNZJLUV kEuD+EQvJiqLHZrAFh+cuy9mPf3lK8KzbrAsXrrd0MfrydpsNb/4NH1DnADC3qL/P/ JJkzzf+qkZ7mPJtwn4mVOstZ4XokLm50gUy70hibpwLWXY5Q8IWSUX4HPXlKxQ5BMe sDJEMjDPYWOcdDZGFZaJJNcLc3Dy/My5Xti0vJeS/HMzIbuTz9+xzjZ0FoxCZYGKkn iTUFoBl9IFnfuhRUXh6x6zyVc4j1P4x/Z5yVrY5ZAMzdJYzLZbs5BHWTBWjsgde80K /JYuFi4b7mB+A== Received: from sofa.misterjones.org ([185.219.108.64] helo=why.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1n6vuD-00H9ok-V5; Mon, 10 Jan 2022 14:44:18 +0000 Date: Mon, 10 Jan 2022 14:44:17 +0000 Message-ID: <87mtk3tzum.wl-maz@kernel.org> From: Marc Zyngier To: Pali =?UTF-8?B?Um9ow6Fy?= Cc: Marek =?UTF-8?B?QmVow7pu?= , Lorenzo Pieralisi , Bjorn Helgaas , linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 23/23] PCI: aardvark: Make main irq_chip structure a static driver structure In-Reply-To: <20220110105324.jud6bzdtmoiuvyas@pali> References: <20220110015018.26359-1-kabel@kernel.org> <20220110015018.26359-24-kabel@kernel.org> <20220110105324.jud6bzdtmoiuvyas@pali> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: pali@kernel.org, kabel@kernel.org, lorenzo.pieralisi@arm.com, helgaas@kernel.org, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Mon, 10 Jan 2022 10:53:24 +0000, Pali Roh=C3=A1r wrote: >=20 > On Monday 10 January 2022 09:28:39 Marc Zyngier wrote: > > On 2022-01-10 01:50, Marek Beh=C3=BAn wrote: > > > Marc Zyngier says [1] that we should use struct irq_chip as a global > > > static struct in the driver. Even though the structure currently > > > contains a dynamic member (parent_device), Marc says [2] that he plans > > > to kill it and make the structure completely static. > > >=20 > > > We have already converted others irq_chip structures in this driver in > > > this way, but we omitted this one because the .name member is > > > dynamically created from device's name, and the name is displayed in > > > sysfs, so changing it would break sysfs ABI. > > >=20 > > > The rationale for changing the name (to "advk-INT") in spite of sysfs > > > ABI, and thus allowing to convert to a static structure, is that after > > > the other changes we made in this series, the IRQ chip is basically > > > something different: it no logner generates ERR and PME interrupts (t= hey > > > are generated by emulated bridge's rp_irq_chip). > >=20 > > There is no 'is spite of the ABI'. If you don't understand why > > we don't break the ABI, you have an even bigger problem. > >=20 > > So NAK to this patch, now and forever. Any change to the structure to > > make it read-only must allow the preservation of the existing names > > when they are generated by the driver. >=20 > Marc, you already presented that you do not like Armada 3720 platform > and that you do not care about it. What I like or not is irrelevant here. What I ask for is that userspace ABIs are not broken. > But please do not slowdown development for this platform. That's quite an accusation. > Arguments about ABIs, breaking it and similar are not relevant here as > this current kernel implementation is broken. And has to be replaced by > a working one. We are doing on it for more than year. > > It really does not make sense to try doing some backward compatibility > with something which is broken by design and does not work. It just take > lot of time without any value. >=20 > We really need to more forward and fix driver as in current state is > PCIe on Armada 3720 unusable. This patch doesn't fix anything. It has the potential to break userspace, and I'm not having any of it. You may not care about backward compatibility, but this is thankfully *not* your pet playground. You can claim that I am doing a bad job. In which case, feel free to submit a patch removing me from the MAINTAINER file, and we can have that discussion. In the meantime, I will continue to oppose these kind of patches that pretend to 'fix' things without adding any value. M. --=20 Without deviation from the norm, progress is not possible.