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 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 9740CC43219 for ; Wed, 1 May 2019 11:14:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7045321670 for ; Wed, 1 May 2019 11:14:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726362AbfEALOe (ORCPT ); Wed, 1 May 2019 07:14:34 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:58200 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725838AbfEALOe (ORCPT ); Wed, 1 May 2019 07:14:34 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 49B7480D; Wed, 1 May 2019 04:14:33 -0700 (PDT) Received: from [10.1.196.50] (e108454-lin.cambridge.arm.com [10.1.196.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 300633F5C1; Wed, 1 May 2019 04:14:31 -0700 (PDT) Subject: Re: [PATCH v2 4/7] irqchip/gic-v3-its: Don't map the MSI page in its_irq_compose_msi_msg() To: Auger Eric , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org Cc: jason@lakedaemon.net, douliyangs@gmail.com, marc.zyngier@arm.com, robin.murphy@arm.com, miquel.raynal@bootlin.com, tglx@linutronix.de, logang@deltatee.com, bigeasy@linutronix.de, linux-rt-users@vger.kernel.org References: <20190429144428.29254-1-julien.grall@arm.com> <20190429144428.29254-5-julien.grall@arm.com> <17855fd3-7f7b-a962-e2bd-c9a0c2dbf765@redhat.com> From: Julien Grall Message-ID: <59ff2eda-74d4-6925-6ed0-8d40e8a892fa@arm.com> Date: Wed, 1 May 2019 12:14:29 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <17855fd3-7f7b-a962-e2bd-c9a0c2dbf765@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30/04/2019 13:34, Auger Eric wrote: > Hi Julien, Hi Eric, Thank you for the review! > > On 4/29/19 4:44 PM, Julien Grall wrote: >> its_irq_compose_msi_msg() may be called from non-preemptible context. >> However, on RT, iommu_dma_map_msi_msg requires to be called from a >> preemptible context. >> >> A recent change split iommu_dma_map_msi_msg() in two new functions: >> one that should be called in preemptible context, the other does >> not have any requirement. >> >> The GICv3 ITS driver is reworked to avoid executing preemptible code in >> non-preemptible context. This can be achieved by preparing the MSI >> maping when allocating the MSI interrupt. > mapping >> >> Signed-off-by: Julien Grall >> >> --- >> Changes in v2: >> - Rework the commit message to use imperative mood >> --- >> drivers/irqchip/irq-gic-v3-its.c | 5 ++++- >> 1 file changed, 4 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c >> index 7577755bdcf4..12ddbcfe1b1e 100644 >> --- a/drivers/irqchip/irq-gic-v3-its.c >> +++ b/drivers/irqchip/irq-gic-v3-its.c >> @@ -1179,7 +1179,7 @@ static void its_irq_compose_msi_msg(struct irq_data *d, struct msi_msg *msg) >> msg->address_hi = upper_32_bits(addr); >> msg->data = its_get_event_id(d); >> >> - iommu_dma_map_msi_msg(d->irq, msg); >> + iommu_dma_compose_msi_msg(irq_data_get_msi_desc(d), msg); >> } >> >> static int its_irq_set_irqchip_state(struct irq_data *d, >> @@ -2566,6 +2566,7 @@ static int its_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, >> { >> msi_alloc_info_t *info = args; >> struct its_device *its_dev = info->scratchpad[0].ptr; >> + struct its_node *its = its_dev->its; >> irq_hw_number_t hwirq; >> int err; >> int i; >> @@ -2574,6 +2575,8 @@ static int its_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, >> if (err) >> return err; >> >> + err = iommu_dma_prepare_msi(info->desc, its->get_msi_base(its_dev)); > Test err as in gicv2m driver? Hmmm yes. Marc, do you want me to respin the patch? Cheers, -- Julien Grall