From ca71228b42a96908eca7658861eafacd227856c9 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 13 Mar 2019 18:07:50 +0000 Subject: [PATCH] arm64: KVM: Always set ICH_HCR_EL2.EN if GICv4 is enabled The normal interrupt flow is not to enable the vgic when no virtual interrupt is to be injected (i.e. the LRs are empty). But when a guest is likely to use GICv4 for LPIs, we absolutely need to switch it on at all times. Otherwise, VLPIs only get delivered when there is something in the LRs, which doesn't happen very often. Reported-by: Nianyao Tang Tested-by: Shameerali Kolothum Thodi Signed-off-by: Marc Zyngier --- virt/kvm/arm/hyp/vgic-v3-sr.c | 4 ++-- virt/kvm/arm/vgic/vgic.c | 14 ++++++++++---- 2 files changed, 12 insertions(+), 6 deletions(-) diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c index 264d92da3240..370bd6c5e6cb 100644 --- a/virt/kvm/arm/hyp/vgic-v3-sr.c +++ b/virt/kvm/arm/hyp/vgic-v3-sr.c @@ -222,7 +222,7 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu) } } - if (used_lrs) { + if (used_lrs || cpu_if->its_vpe.its_vm) { int i; u32 elrsr; @@ -247,7 +247,7 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu) u64 used_lrs = vcpu->arch.vgic_cpu.used_lrs; int i; - if (used_lrs) { + if (used_lrs || cpu_if->its_vpe.its_vm) { write_gicreg(cpu_if->vgic_hcr, ICH_HCR_EL2); for (i = 0; i < used_lrs; i++) diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c index abd9c7352677..3af69f2a3866 100644 --- a/virt/kvm/arm/vgic/vgic.c +++ b/virt/kvm/arm/vgic/vgic.c @@ -867,15 +867,21 @@ void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu) * either observe the new interrupt before or after doing this check, * and introducing additional synchronization mechanism doesn't change * this. + * + * Note that we still need to go through the whole thing if anything + * can be directly injected (GICv4). */ - if (list_empty(&vcpu->arch.vgic_cpu.ap_list_head)) + if (list_empty(&vcpu->arch.vgic_cpu.ap_list_head) && + !vgic_supports_direct_msis(vcpu->kvm)) return; DEBUG_SPINLOCK_BUG_ON(!irqs_disabled()); - raw_spin_lock(&vcpu->arch.vgic_cpu.ap_list_lock); - vgic_flush_lr_state(vcpu); - raw_spin_unlock(&vcpu->arch.vgic_cpu.ap_list_lock); + if (!list_empty(&vcpu->arch.vgic_cpu.ap_list_head)) { + raw_spin_lock(&vcpu->arch.vgic_cpu.ap_list_lock); + vgic_flush_lr_state(vcpu); + raw_spin_unlock(&vcpu->arch.vgic_cpu.ap_list_lock); + } if (can_access_vgic_from_kernel()) vgic_restore_state(vcpu);