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=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 43552C4332B for ; Thu, 19 Mar 2020 16:16:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 11CC820836 for ; Thu, 19 Mar 2020 16:16:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="KgBlCxjb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728078AbgCSQQt (ORCPT ); Thu, 19 Mar 2020 12:16:49 -0400 Received: from us-smtp-delivery-74.mimecast.com ([63.128.21.74]:37997 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727885AbgCSQQs (ORCPT ); Thu, 19 Mar 2020 12:16:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1584634607; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6L0/RW+VybIY9YlBcySb8qcqc4y1OrahRYFLfqqgB0g=; b=KgBlCxjbqbYoiqatd3+NrXxrG1HfjarWdYT+tNn9EAWFB3JdUaqdCsiZ0OqukyF7W9ENBs wbprPRpodh4ZFVA/gq0B0DgZupq2QRUSMDn3Gfijzrbc2m7lLT4NrMjKtvA4m20vKdIq8F LTWjWZqJHiWl0L/1WI/di8SoYGAHSFQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-378-vX5yTDLbP-aj3TcYLVcNAw-1; Thu, 19 Mar 2020 12:16:43 -0400 X-MC-Unique: vX5yTDLbP-aj3TcYLVcNAw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 129021005516; Thu, 19 Mar 2020 16:16:41 +0000 (UTC) Received: from [10.36.113.142] (ovpn-113-142.ams2.redhat.com [10.36.113.142]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D7D6F60BF1; Thu, 19 Mar 2020 16:16:37 +0000 (UTC) Subject: Re: [PATCH v5 19/23] KVM: arm64: GICv4.1: Allow SGIs to switch between HW and SW interrupts To: Marc Zyngier , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Lorenzo Pieralisi , Jason Cooper , Robert Richter , Thomas Gleixner , Zenghui Yu , James Morse , Julien Thierry , Suzuki K Poulose References: <20200304203330.4967-1-maz@kernel.org> <20200304203330.4967-20-maz@kernel.org> From: Auger Eric Message-ID: <8a6cf87a-7eee-5502-3b54-093ea0ab5e2d@redhat.com> Date: Thu, 19 Mar 2020 17:16:36 +0100 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: <20200304203330.4967-20-maz@kernel.org> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Marc, On 3/4/20 9:33 PM, Marc Zyngier wrote: > In order to let a guest buy in the new, active-less SGIs, we > need to be able to switch between the two modes. > > Handle this by stopping all guest activity, transfer the state > from one mode to the other, and resume the guest. Nothing calls > this code so far, but a later patch will plug it into the MMIO > emulation. > > Signed-off-by: Marc Zyngier > --- > include/kvm/arm_vgic.h | 3 ++ > virt/kvm/arm/vgic/vgic-v4.c | 94 +++++++++++++++++++++++++++++++++++++ > virt/kvm/arm/vgic/vgic.h | 1 + > 3 files changed, 98 insertions(+) > > diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h > index 63457908c9c4..69f4164d6477 100644 > --- a/include/kvm/arm_vgic.h > +++ b/include/kvm/arm_vgic.h > @@ -231,6 +231,9 @@ struct vgic_dist { > /* distributor enabled */ > bool enabled; > > + /* Wants SGIs without active state */ > + bool nassgireq; > + > struct vgic_irq *spis; > > struct vgic_io_device dist_iodev; > diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c > index c2fcde104ea2..a65dc1c85363 100644 > --- a/virt/kvm/arm/vgic/vgic-v4.c > +++ b/virt/kvm/arm/vgic/vgic-v4.c > @@ -97,6 +97,100 @@ static irqreturn_t vgic_v4_doorbell_handler(int irq, void *info) > return IRQ_HANDLED; > } > > +static void vgic_v4_sync_sgi_config(struct its_vpe *vpe, struct vgic_irq *irq) > +{ > + vpe->sgi_config[irq->intid].enabled = irq->enabled; > + vpe->sgi_config[irq->intid].group = irq->group; > + vpe->sgi_config[irq->intid].priority = irq->priority; > +} > + > +static void vgic_v4_enable_vsgis(struct kvm_vcpu *vcpu) > +{ > + struct its_vpe *vpe = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe; > + int i; > + > + /* > + * With GICv4.1, every virtual SGI can be directly injected. So > + * let's pretend that they are HW interrupts, tied to a host > + * IRQ. The SGI code will do its magic. > + */ > + for (i = 0; i < VGIC_NR_SGIS; i++) { > + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, i); > + struct irq_desc *desc; > + int ret; Is is safe without holding the irq->irq_lock? > + > + if (irq->hw) { > + vgic_put_irq(vcpu->kvm, irq); > + continue; > + } > + > + irq->hw = true; > + irq->host_irq = irq_find_mapping(vpe->sgi_domain, i); > + > + /* Transfer the full irq state to the vPE */ > + vgic_v4_sync_sgi_config(vpe, irq); > + desc = irq_to_desc(irq->host_irq); > + ret = irq_domain_activate_irq(irq_desc_get_irq_data(desc), > + false); > + if (!WARN_ON(ret)) { > + /* Transfer pending state */ > + ret = irq_set_irqchip_state(irq->host_irq, > + IRQCHIP_STATE_PENDING, > + irq->pending_latch); > + WARN_ON(ret); > + irq->pending_latch = false; > + } > + > + vgic_put_irq(vcpu->kvm, irq); > + } > +} > + > +static void vgic_v4_disable_vsgis(struct kvm_vcpu *vcpu) > +{ > + int i; > + > + for (i = 0; i < VGIC_NR_SGIS; i++) { > + struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, i); > + struct irq_desc *desc; > + int ret; > + > + if (!irq->hw) { > + vgic_put_irq(vcpu->kvm, irq); > + continue; > + } > + > + irq->hw = false; > + ret = irq_get_irqchip_state(irq->host_irq, > + IRQCHIP_STATE_PENDING, > + &irq->pending_latch); > + WARN_ON(ret); > + > + desc = irq_to_desc(irq->host_irq); > + irq_domain_deactivate_irq(irq_desc_get_irq_data(desc)); > + > + vgic_put_irq(vcpu->kvm, irq); > + } > +} > + > +/* Must be called with the kvm lock held */ > +void vgic_v4_configure_vsgis(struct kvm *kvm) > +{ > + struct vgic_dist *dist = &kvm->arch.vgic; > + struct kvm_vcpu *vcpu; > + int i; > + > + kvm_arm_halt_guest(kvm); > + > + kvm_for_each_vcpu(i, vcpu, kvm) { > + if (dist->nassgireq) > + vgic_v4_enable_vsgis(vcpu); > + else > + vgic_v4_disable_vsgis(vcpu); > + } > + > + kvm_arm_resume_guest(kvm); > +} > + > /** > * vgic_v4_init - Initialize the GICv4 data structures > * @kvm: Pointer to the VM being initialized > diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h > index c7fefd6b1c80..769e4802645e 100644 > --- a/virt/kvm/arm/vgic/vgic.h > +++ b/virt/kvm/arm/vgic/vgic.h > @@ -316,5 +316,6 @@ void vgic_its_invalidate_cache(struct kvm *kvm); > bool vgic_supports_direct_msis(struct kvm *kvm); > int vgic_v4_init(struct kvm *kvm); > void vgic_v4_teardown(struct kvm *kvm); > +void vgic_v4_configure_vsgis(struct kvm *kvm); > > #endif > Thanks Eric