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 61861C433EF for ; Wed, 27 Apr 2022 19:08:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231897AbiD0TLN (ORCPT ); Wed, 27 Apr 2022 15:11:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46960 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232405AbiD0TLC (ORCPT ); Wed, 27 Apr 2022 15:11:02 -0400 Received: from mxout01.lancloud.ru (mxout01.lancloud.ru [45.84.86.81]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DB8F880227 for ; Wed, 27 Apr 2022 11:59:43 -0700 (PDT) Received: from LanCloud DKIM-Filter: OpenDKIM Filter v2.11.0 mxout01.lancloud.ru E307C20B0E77 Received: from LanCloud Received: from LanCloud Received: from LanCloud From: Sergey Shtylyov Subject: Re: [PATCH v2] platform: finally disallow IRQ0 in platform_get_irq() and its ilk To: Greg Kroah-Hartman CC: "Rafael J. Wysocki" , , Marc Zyngier References: <025679e1-1f0a-ae4b-4369-01164f691511@omp.ru> Organization: Open Mobile Platform Message-ID: Date: Wed, 27 Apr 2022 21:59:41 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [192.168.11.198] X-ClientProxiedBy: LFEXT01.lancloud.ru (fd00:f066::141) To LFEX1907.lancloud.ru (fd00:f066::207) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello! On 4/26/22 1:46 PM, Greg Kroah-Hartman wrote: >> The commit a85a6c86c25b ("driver core: platform: Clarify that IRQ 0 is >> invalid") only calls WARN() when IRQ0 is about to be returned, however >> using IRQ0 is considered invalid (according to Linus) outside the arch/ >> code where it's used by the i8253 drivers. Many driver subsystems treat >> 0 specially (e.g. as an indication of the polling mode by libata), so >> the users of platform_get_irq[_byname]() in them would have to filter >> out IRQ0 explicitly and this (quite obviously) doesn't scale... >> Let's finally get this straight and return -EINVAL instead of IRQ0! >> >> Fixes: a85a6c86c25b ("driver core: platform: Clarify that IRQ 0 is invalid") >> Signed-off-by: Sergey Shtylyov >> Acked-by: Marc Zyngier [...] > Ok, let's try this now. Well, better late than never! :-) > Worst case, we revert it later :) Please just don't revert it outright on the 1st issue report -- give me time to look at the issue(s) reported... BTW, I've CC'ed you on the SH patch that avoids using IRQ0. Please help to merge it (v1/v2 were posted on February 11th and there was no motion since then)! > thanks, > > greg k-h MBR, Sergey