From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932740AbaHYNbz (ORCPT ); Mon, 25 Aug 2014 09:31:55 -0400 Received: from mail-wi0-f180.google.com ([209.85.212.180]:54274 "EHLO mail-wi0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932300AbaHYN2h (ORCPT ); Mon, 25 Aug 2014 09:28:37 -0400 From: Eric Auger To: eric.auger@st.com, eric.auger@linaro.org, christoffer.dall@linaro.org, marc.zyngier@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, alex.williamson@redhat.com, joel.schopp@amd.com, kim.phillips@freescale.com Cc: linux-kernel@vger.kernel.org, patches@linaro.org, will.deacon@arm.com, a.motakis@virtualopensystems.com, a.rigo@virtualopensystems.com, john.liuli@huawei.com Subject: [RFC 1/9] KVM: ARM: VGIC: fix multiple injection of level sensitive forwarded IRQ Date: Mon, 25 Aug 2014 15:27:36 +0200 Message-Id: <1408973264-30384-2-git-send-email-eric.auger@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1408973264-30384-1-git-send-email-eric.auger@linaro.org> References: <1408973264-30384-1-git-send-email-eric.auger@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Fix multiple injection of level sensitive forwarded IRQs. With current code, the second injection fails since the state bitmaps are not reset (process_maintenance is not called anymore). New implementation consists in fully bypassing the vgic state management for forwarded IRQ (checks are ignored in vgic_update_irq_pending). This obviously assumes the forwarded IRQ is injected from kernel side. --- It was attempted to reset the states in __kvm_vgic_sync_hwstate, checking the emptied LR of forwarded IRQ. However surprisingly this solution does not seem to work. Some times, a new forwarded IRQ injection is observed while the LR of the previous instance was not observed as empty. Signed-off-by: Eric Auger --- include/kvm/arm_vgic.h | 1 + virt/kvm/arm/vgic.c | 9 +++++++-- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 743020f..3da244f 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -177,6 +177,7 @@ struct vgic_dist { unsigned long irq_pending_on_cpu; struct rb_root irq_phys_map; + spinlock_t rb_tree_lock; #endif }; diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 0007300..195c10c 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1517,14 +1517,18 @@ static bool vgic_update_irq_pending(struct kvm *kvm, int cpuid, int edge_triggered, level_triggered; int enabled; bool ret = true; + bool is_forwarded; spin_lock(&dist->lock); vcpu = kvm_get_vcpu(kvm, cpuid); + is_forwarded = (vgic_get_phys_irq(vcpu, irq_num) >0); + edge_triggered = vgic_irq_is_edge(vcpu, irq_num); level_triggered = !edge_triggered; - if (!vgic_validate_injection(vcpu, irq_num, level)) { + if (!is_forwarded && + !vgic_validate_injection(vcpu, irq_num, level)) { ret = false; goto out; } @@ -1557,7 +1561,8 @@ static bool vgic_update_irq_pending(struct kvm *kvm, int cpuid, goto out; } - if (level_triggered && vgic_irq_is_queued(vcpu, irq_num)) { + if (!is_forwarded && + level_triggered && vgic_irq_is_queued(vcpu, irq_num)) { /* * Level interrupt in progress, will be picked up * when EOId. -- 1.9.1