From 9c7bfc288c71068ab323b802dba2eb87fd08b127 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 9 Jun 2017 12:49:40 +0100 Subject: KVM: arm64: vgic-v3: Enable trapping of Group-1 system registers In order to be able to trap Group-1 GICv3 system registers, we need to set ICH_HCR_EL2.TALL1 before entering the guest. This is conditionally done after having restored the guest's state, and cleared on exit. Tested-by: Alexander Graf Acked-by: David Daney Acked-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- include/linux/irqchip/arm-gic-v3.h | 1 + virt/kvm/arm/hyp/vgic-v3-sr.c | 11 +++++++++++ virt/kvm/arm/vgic/vgic-v3.c | 4 ++++ 3 files changed, 16 insertions(+) diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index 1f458ac6f494..6b05d2ac8c54 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_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/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c index f031e8f088ae..a2a62f030341 100644 --- a/virt/kvm/arm/hyp/vgic-v3-sr.c +++ b/virt/kvm/arm/hyp/vgic-v3-sr.c @@ -258,6 +258,9 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu) cpu_if->vgic_ap1r[0] = __vgic_v3_read_ap1rn(0); } } else { + if (static_branch_unlikely(&vgic_v3_cpuif_trap)) + write_gicreg(0, ICH_HCR_EL2); + cpu_if->vgic_elrsr = 0xffff; cpu_if->vgic_ap0r[0] = 0; cpu_if->vgic_ap0r[1] = 0; @@ -330,6 +333,14 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu) for (i = 0; i < used_lrs; i++) __gic_v3_set_lr(cpu_if->vgic_lr[i], i); + } else { + /* + * If we need to trap system registers, we must write + * ICH_HCR_EL2 anyway, even if no interrupts are being + * injected, + */ + if (static_branch_unlikely(&vgic_v3_cpuif_trap)) + write_gicreg(cpu_if->vgic_hcr, ICH_HCR_EL2); } /* diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c index fac6e23cd0b3..722bdebdfbb5 100644 --- a/virt/kvm/arm/vgic/vgic-v3.c +++ b/virt/kvm/arm/vgic/vgic-v3.c @@ -21,6 +21,8 @@ #include "vgic.h" +static bool group1_trap; + void vgic_v3_set_underflow(struct kvm_vcpu *vcpu) { struct vgic_v3_cpu_if *cpuif = &vcpu->arch.vgic_cpu.vgic_v3; @@ -258,6 +260,8 @@ void vgic_v3_enable(struct kvm_vcpu *vcpu) /* Get the show on the road... */ vgic_v3->vgic_hcr = ICH_HCR_EN; + if (group1_trap) + vgic_v3->vgic_hcr |= ICH_HCR_TALL1; } int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq) -- cgit