From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1425622AbcBRIqM (ORCPT ); Thu, 18 Feb 2016 03:46:12 -0500 Received: from mout01.posteo.de ([185.67.36.65]:39780 "EHLO mout01.posteo.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1424633AbcBRIqH (ORCPT ); Thu, 18 Feb 2016 03:46:07 -0500 Subject: Re: [PATCH] rtc: max77686: fix irqf_oneshot.cocci warnings To: Krzysztof Kozlowski , ldewangan@nvidia.com References: <1455782816-5814-1-git-send-email-valentin.rothberg@posteo.net> <56C57D1E.805@samsung.com> Cc: kbuild-all@01.org, alexandre.belloni@free-electrons.com, javier@osg.samsung.com, cw00.choi@samsung.com, a.zummo@towertech.it, linux-kernel@vger.kernel.org, rtc-linux@googlegroups.com, kbuild test robot From: Valentin Rothberg Message-ID: <56C584CC.2000104@posteo.net> Date: Thu, 18 Feb 2016 09:46:04 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <56C57D1E.805@samsung.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Krzysztof, On 2/18/16 9:13 AM, Krzysztof Kozlowski wrote: > On 18.02.2016 17:06, Valentin Rothberg wrote: >> From: kbuild test robot >> >> Since commit 1c6c69525b40 ("genirq: Reject bogus threaded irq requests") >> threaded IRQs without a primary handler need to be requested with >> IRQF_ONESHOT, otherwise the request will fail. >> >> So pass the IRQF_ONESHOT flag in this case. >> >> Generated by: scripts/coccinelle/misc/irqf_oneshot.cocci >> >> CC: Laxman Dewangan >> Signed-off-by: Fengguang Wu >> Signed-off-by: Valentin Rothberg >> --- >> drivers/rtc/rtc-max77686.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> > > Nack, because: > 1. AFAIR this is a false positive. Looking at kernel/irq/manage.c +1250 such requests will be rejected unconditionally when the primary handler is NULL, except when the chip is marked to be oneshot safe. Is there another semantic that I am not aware of? In case the script produces false positives, I will change it immediately. > 2. Was it tested? Was it reproduced? Was the bug actually spotted or > just coccicheck pointed this and you assumed that "request will fail"? > > Coccicheck is a great tool... but not necessarily for pointing run-time > bugs. I did not test it. To me the issue rather seems seems like something where Coccinelle is really good at, static analysis. Kind regards, Valentin