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 D4B18C433F5 for ; Fri, 10 Dec 2021 19:01:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245735AbhLJTFC (ORCPT ); Fri, 10 Dec 2021 14:05:02 -0500 Received: from mxout04.lancloud.ru ([45.84.86.114]:57176 "EHLO mxout04.lancloud.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237589AbhLJTEv (ORCPT ); Fri, 10 Dec 2021 14:04:51 -0500 Received: from LanCloud DKIM-Filter: OpenDKIM Filter v2.11.0 mxout04.lancloud.ru F2B7020A73F8 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 , Sergei Shtylyov CC: Damien Le Moal , , , Hans de Goede , Jens Axboe References: <20211209145937.77719-1-andriy.shevchenko@linux.intel.com> <9e6b2e9a-e958-0c14-6570-135607041978@omp.ru> <6c03ffef-b2e0-16ba-35f3-206af2a611d2@gmail.com> From: Sergey Shtylyov Organization: Open Mobile Platform Message-ID: <9d688cd8-99e3-0265-06aa-d44597e7686c@omp.ru> Date: Fri, 10 Dec 2021 22:01:04 +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-kernel@vger.kernel.org On 12/10/21 8:59 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... >>> >>> So, have you seen this warning (being reported) related to libahci_platform? >> >> No (as if you need to really see this while it's obvious from the code review). >> >>> If no, what we are discussing about then? The workaround is redundant and >> >> I don't know. :-) Your arguments so far seem bogus (sorry! :-))... > > It seems you haven't got them at all. The problems of platform_get_irq() et al > shouldn't be worked around in the callers. I have clearly explained to you what I'm working around there. If that wasn't clear enough, I don't want to continue this talk anymore. Good luck with your patch (not this one). [...] MBR, Sergey