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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EAF73C10F00 for ; Thu, 21 Mar 2019 13:21:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C3F4E218FF for ; Thu, 21 Mar 2019 13:21:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728330AbfCUNVw (ORCPT ); Thu, 21 Mar 2019 09:21:52 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:5169 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728049AbfCUNVw (ORCPT ); Thu, 21 Mar 2019 09:21:52 -0400 Received: from DGGEMS410-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 516952E2750DC0DBCDD2; Thu, 21 Mar 2019 21:21:49 +0800 (CST) Received: from [127.0.0.1] (10.74.177.192) by DGGEMS410-HUB.china.huawei.com (10.3.19.210) with Microsoft SMTP Server id 14.3.408.0; Thu, 21 Mar 2019 21:21:41 +0800 Subject: Re: [PATCH] mbigen: don't clear eventid when free_irq To: Marc Zyngier References: <20190321091135.5574b496@why.wild-wind.fr.eu.org> CC: Thomas Gleixner , Jason Cooper , "linux-kernel@vger.kernel.org" , "Liyou (leeyou, RTOS)" , "Joey Yan(Bo)" , "Xiaowei (C)" , "zhanghan (Q)" , Yangyingliang , yaohongbo , Linuxarm From: Chen Jianguo Message-ID: Date: Thu, 21 Mar 2019 21:21:40 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <20190321091135.5574b496@why.wild-wind.fr.eu.org> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.74.177.192] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Marc On 2019/3/21 17:11, Marc Zyngier wrote: > On Sat, 16 Mar 2019 11:15:03 +0000 > chenjianguo wrote: > >> From: Jianguo Chen >> >> mbigen_write_msg clears eventid bits of a mbigen register >> when free a interrupt, because msi_domain_deactivate memset >> struct msg to zero. Then multiple mbigen pins with zero eventid >> will report the same interrupt number. >> >> The eventid clear call trace: >> free_irq >> __free_irq >> irq_shutdown >> irq_domain_deactivate_irq >> __irq_domain_deactivate_irq >> __irq_domain_deactivate_irq >> msi_domain_deactivate >> platform_msi_write_msg >> mbigen_write_msg >> >> Signed-off-by: Jianguo Chen >> --- >> drivers/irqchip/irq-mbigen.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/irqchip/irq-mbigen.c b/drivers/irqchip/irq-mbigen.c >> index 567b29c..fad7291 100644 >> --- a/drivers/irqchip/irq-mbigen.c >> +++ b/drivers/irqchip/irq-mbigen.c >> @@ -161,6 +161,9 @@ static void mbigen_write_msg(struct msi_desc *desc, >> struct msi_msg *msg) >> void __iomem *base = d->chip_data; >> u32 val; >> >> + if (!msg->address_lo && !msg->address_hi) >> + return; >> + >> base += get_mbigen_vec_reg(d->hwirq); >> val = readl_relaxed(base); >> > > For whatever reason, I couldn't apply this patch (even when fishing a > copy of this email from the archives). It seems to be corrupted is > various ways, so I had to write the patch from scratch, which is not the > most reliable way to work. Good thing this was something trivial, I > wouldn't do it for something more complicated. > > In the future, please make sure to use 'git send-email' to send your > patches, as it is known to work correctly. > > Thanks, > > M. > Mbigen vector register and pin structure shows as below: event id 0 1 2 127 vector register reg0 reg1 reg2 reg127 | | | | MBIGEN pin0 pin1 pin2 ... pin127 |-----|-----|-----|-----| | | | | | device interrupt num0 num1 num2 num127 Suppose a device driver requested irq num0 and num1 at the beginning, and for some reason it freed irq num1, mbigen_write_msg will write reg1 with event id 0. Then the pin1 probably mistakenly report interrupt num0 to device driver if there is a signal on the pin. event id 0 0 2 127 vector register reg0 reg1 reg2 reg127 | | | | MBIGEN pin0 pin1 pin2 ... pin127 |-----|-----|-----|-----| | | | | | device interrup num0 num1 num2 num127 Thanks, Jianguo Chen