From abf55766f7b062234083ff612446ff8d47e2417e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 9 Jun 2017 12:49:45 +0100 Subject: [PATCH] KVM: arm64: vgic-v3: Enable trapping of Group-0 system registers In order to be able to trap Group-0 GICv3 system registers, we need to set ICH_HCR_EL2.TALL0 begore entering the guest. This is conditionnaly done after having restored the guest's state, and cleared on exit. Tested-by: Alexander Graf Acked-by: David Daney Acked-by: Christoffer Dall Reviewed-by: Eric Auger Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- include/linux/irqchip/arm-gic-v3.h | 1 + virt/kvm/arm/vgic/vgic-v3.c | 5 ++++- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index 6b05d2ac8c54..c7f31a962cfc 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -417,6 +417,7 @@ #define ICH_HCR_EN (1 << 0) #define ICH_HCR_UIE (1 << 1) +#define ICH_HCR_TALL0 (1 << 11) #define ICH_HCR_TALL1 (1 << 12) #define ICH_HCR_EOIcount_SHIFT 27 #define ICH_HCR_EOIcount_MASK (0x1f << ICH_HCR_EOIcount_SHIFT) diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c index 4b2b62b73470..39046ee5be25 100644 --- a/virt/kvm/arm/vgic/vgic-v3.c +++ b/virt/kvm/arm/vgic/vgic-v3.c @@ -21,6 +21,7 @@ #include "vgic.h" +static bool group0_trap; static bool group1_trap; void vgic_v3_set_underflow(struct kvm_vcpu *vcpu) @@ -260,6 +261,8 @@ void vgic_v3_enable(struct kvm_vcpu *vcpu) /* Get the show on the road... */ vgic_v3->vgic_hcr = ICH_HCR_EN; + if (group0_trap) + vgic_v3->vgic_hcr |= ICH_HCR_TALL0; if (group1_trap) vgic_v3->vgic_hcr |= ICH_HCR_TALL1; } @@ -492,7 +495,7 @@ int vgic_v3_probe(const struct gic_kvm_info *info) if (kvm_vgic_global_state.vcpu_base == 0) kvm_info("disabling GICv2 emulation\n"); - if (group1_trap) { + if (group0_trap || group1_trap) { kvm_info("GICv3 sysreg trapping enabled (reduced performance)\n"); static_branch_enable(&vgic_v3_cpuif_trap); } -- 2.20.1