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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 E6A25C433DF for ; Fri, 29 May 2020 04:07:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C8295214D8 for ; Fri, 29 May 2020 04:07:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390865AbgE2EHy (ORCPT ); Fri, 29 May 2020 00:07:54 -0400 Received: from szxga07-in.huawei.com ([45.249.212.35]:39146 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727094AbgE2EHx (ORCPT ); Fri, 29 May 2020 00:07:53 -0400 Received: from DGGEMS405-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id B1A4569FBB21838E7DBA; Fri, 29 May 2020 12:07:50 +0800 (CST) Received: from [10.173.222.27] (10.173.222.27) by DGGEMS405-HUB.china.huawei.com (10.3.19.205) with Microsoft SMTP Server id 14.3.487.0; Fri, 29 May 2020 12:07:42 +0800 Subject: Re: [PATCH] irqchip/gic-v3-its: Don't try to move a disabled irq To: Ali Saidi , Thomas Gleixner , Jason Cooper , Marc Zyngier , CC: , , , , References: <20200529015501.15771-1-alisaidi@amazon.com> From: Zenghui Yu Message-ID: Date: Fri, 29 May 2020 12:07:31 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.2.0 MIME-Version: 1.0 In-Reply-To: <20200529015501.15771-1-alisaidi@amazon.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.173.222.27] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 2020/5/29 9:55, Ali Saidi wrote: > If an interrupt is disabled the ITS driver has sent a discard removing > the DeviceID and EventID from the ITT. After this occurs it can't be > moved to another collection with a MOVI and a command error occurs if > attempted. Before issuing the MOVI command make sure that the IRQ isn't > disabled and change the activate code to try and use the previous > affinity. > > Signed-off-by: Ali Saidi > --- > drivers/irqchip/irq-gic-v3-its.c | 18 +++++++++++++++--- > 1 file changed, 15 insertions(+), 3 deletions(-) > > diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c > index 124251b0ccba..1235dd9a2fb2 100644 > --- a/drivers/irqchip/irq-gic-v3-its.c > +++ b/drivers/irqchip/irq-gic-v3-its.c > @@ -1540,7 +1540,11 @@ static int its_set_affinity(struct irq_data *d, const struct cpumask *mask_val, > /* don't set the affinity when the target cpu is same as current one */ > if (cpu != its_dev->event_map.col_map[id]) { > target_col = &its_dev->its->collections[cpu]; > - its_send_movi(its_dev, target_col, id); > + > + /* If the IRQ is disabled a discard was sent so don't move */ > + if (!irqd_irq_disabled(d)) > + its_send_movi(its_dev, target_col, id); It looks to me that if the IRQ is disabled, we mask the enable bit in the corresponding LPI configuration table entry, but not sending DISCARD to remove the DevID/EventID mapping. And moving a disabled LPI is actually allowed by the GIC architecture, right? > + > its_dev->event_map.col_map[id] = cpu; > irq_data_update_effective_affinity(d, cpumask_of(cpu)); > } > @@ -3439,8 +3443,16 @@ static int its_irq_domain_activate(struct irq_domain *domain, > if (its_dev->its->numa_node >= 0) > cpu_mask = cpumask_of_node(its_dev->its->numa_node); > > - /* Bind the LPI to the first possible CPU */ > - cpu = cpumask_first_and(cpu_mask, cpu_online_mask); > + /* If the cpu set to a different CPU that is still online use it */ > + cpu = its_dev->event_map.col_map[event]; > + > + cpumask_and(cpu_mask, cpu_mask, cpu_online_mask); > + > + if (!cpumask_test_cpu(cpu, cpu_mask)) { > + /* Bind the LPI to the first possible CPU */ > + cpu = cpumask_first(cpu_mask); > + } I'd like to know what actual problem you had seen and the way to reproduce it :-) Thanks, Zenghui