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 12AEEC43219 for ; Tue, 30 Apr 2019 12:35:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DFE322080C for ; Tue, 30 Apr 2019 12:34:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727943AbfD3Me6 (ORCPT ); Tue, 30 Apr 2019 08:34:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45086 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726015AbfD3Me4 (ORCPT ); Tue, 30 Apr 2019 08:34:56 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B2F173087921; Tue, 30 Apr 2019 12:34:55 +0000 (UTC) Received: from [10.36.116.17] (ovpn-116-17.ams2.redhat.com [10.36.116.17]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 1AC46600C2; Tue, 30 Apr 2019 12:34:52 +0000 (UTC) Subject: Re: [PATCH v2 4/7] irqchip/gic-v3-its: Don't map the MSI page in its_irq_compose_msi_msg() To: Julien Grall , 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> From: Auger Eric Message-ID: <17855fd3-7f7b-a962-e2bd-c9a0c2dbf765@redhat.com> Date: Tue, 30 Apr 2019 14:34:51 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <20190429144428.29254-5-julien.grall@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Tue, 30 Apr 2019 12:34:55 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Julien, 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? > + > for (i = 0; i < nr_irqs; i++) { > err = its_irq_gic_domain_alloc(domain, virq + i, hwirq + i); > if (err) > Besides Reviewed-by: Eric Auger Thanks Eric