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 7270EC433F5 for ; Fri, 10 Dec 2021 11:19:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237854AbhLJLXa (ORCPT ); Fri, 10 Dec 2021 06:23:30 -0500 Received: from mxout01.lancloud.ru ([45.84.86.81]:59736 "EHLO mxout01.lancloud.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237710AbhLJLXa (ORCPT ); Fri, 10 Dec 2021 06:23:30 -0500 Received: from LanCloud DKIM-Filter: OpenDKIM Filter v2.11.0 mxout01.lancloud.ru B67E920E6B12 Received: from LanCloud Received: from LanCloud Received: from LanCloud Subject: Re: [PATCH v1 1/2] ata: libahci_platform: Get rid of dup message when IRQ can't be retrieved To: Andy Shevchenko CC: Damien Le Moal , , , Hans de Goede , Jens Axboe References: <20211209145937.77719-1-andriy.shevchenko@linux.intel.com> From: Sergey Shtylyov Organization: Open Mobile Platform Message-ID: <9e6b2e9a-e958-0c14-6570-135607041978@omp.ru> Date: Fri, 10 Dec 2021 14:19:52 +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: LFEXT02.lancloud.ru (fd00:f066::142) To LFEX1907.lancloud.ru (fd00:f066::207) Precedence: bulk List-ID: X-Mailing-List: linux-ide@vger.kernel.org On 12/10/21 1:46 PM, Andy Shevchenko wrote: >>>> platform_get_irq() will print a message when it fails. >>>> No need to repeat this. >>>> >>>> While at it, drop redundant check for 0 as platform_get_irq() spills >>>> out a big WARN() in such case. >>> >>> The reason you should be able to remove the "if (!irq)" test is that >>> platform_get_irq() never returns 0. At least, that is what the function kdoc >>> says. But looking at platform_get_irq_optional(), which is called by >>> platform_get_irq(), the out label is: >>> >>> WARN(ret == 0, "0 is an invalid IRQ number\n"); >>> return ret; >>> >>> So 0 will be returned as-is. That is rather weird. That should be fixed to >>> return -ENXIO: >>> >>> if (WARN(ret == 0, "0 is an invalid IRQ number\n")) >>> return -ENXIO; >>> return ret; >> >> My unmerged patch (https://marc.info/?l=linux-kernel&m=163623041902285) does this >> but returns -EINVAL instead. >> >>> Otherwise, I do not think that removing the "if (!irq)" hunk is safe. no ? >> >> Of course it isn't... > > It's unsubstantiated statement. The vIRQ 0 shouldn't be returned by any of > those API calls. We do _not_ know what needs to be fixed, that's the problem, and that's why the WARN() is there... > If it is the case, go and fix them, no need to workaround > in each of the callers. There's a need to work around as long as IRQ0 ican be returned, otherwise we get partly functioning or non-functioning drivers... MBR, Sergey