From 59da1cbfd840d69bd7a310249924da3fc202c417 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 9 Jun 2017 12:49:33 +0100 Subject: [PATCH] KVM: arm64: vgic-v3: Add hook to handle guest GICv3 sysreg accesses at EL2 In order to start handling guest access to GICv3 system registers, let's add a hook that will get called when we trap a system register access. This is gated by a new static key (vgic_v3_cpuif_trap). Tested-by: Alexander Graf Acked-by: David Daney Reviewed-by: Eric Auger Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm64/include/asm/kvm_hyp.h | 1 + arch/arm64/kvm/hyp/switch.c | 14 ++++++++++++++ include/kvm/arm_vgic.h | 1 + virt/kvm/arm/hyp/vgic-v3-sr.c | 38 ++++++++++++++++++++++++++++++++++++++ virt/kvm/arm/vgic/vgic-v3.c | 2 ++ 5 files changed, 56 insertions(+) diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h index b18e852..4572a9b5 100644 --- a/arch/arm64/include/asm/kvm_hyp.h +++ b/arch/arm64/include/asm/kvm_hyp.h @@ -127,6 +127,7 @@ int __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu); void __vgic_v3_save_state(struct kvm_vcpu *vcpu); void __vgic_v3_restore_state(struct kvm_vcpu *vcpu); +int __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu); void __timer_save_state(struct kvm_vcpu *vcpu); void __timer_restore_state(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index e5f089d..945e79c 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -350,6 +350,20 @@ again: } } + if (static_branch_unlikely(&vgic_v3_cpuif_trap) && + exit_code == ARM_EXCEPTION_TRAP && + (kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 || + kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_CP15_32)) { + int ret = __vgic_v3_perform_cpuif_access(vcpu); + + if (ret == 1) { + __skip_instr(vcpu); + goto again; + } + + /* 0 falls through to be handled out of EL2 */ + } + fp_enabled = __fpsimd_enabled(); __sysreg_save_guest_state(guest_ctxt); diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 2d923a6..34dba51 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -292,6 +292,7 @@ struct vgic_cpu { }; extern struct static_key_false vgic_v2_cpuif_trap; +extern struct static_key_false vgic_v3_cpuif_trap; int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write); void kvm_vgic_early_init(struct kvm *kvm); diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c index 3dd8f0c..e6c05b9 100644 --- a/virt/kvm/arm/hyp/vgic-v3-sr.c +++ b/virt/kvm/arm/hyp/vgic-v3-sr.c @@ -19,6 +19,7 @@ #include #include +#include #include #define vtr_to_max_lr_idx(v) ((v) & 0xf) @@ -371,3 +372,40 @@ void __hyp_text __vgic_v3_write_vmcr(u32 vmcr) { write_gicreg(vmcr, ICH_VMCR_EL2); } + +#ifdef CONFIG_ARM64 + +int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu) +{ + int rt; + u32 esr; + u32 vmcr; + void (*fn)(struct kvm_vcpu *, u32, int); + bool is_read; + u32 sysreg; + + esr = kvm_vcpu_get_hsr(vcpu); + if (vcpu_mode_is_32bit(vcpu)) { + if (!kvm_condition_valid(vcpu)) + return 1; + + sysreg = esr_cp15_to_sysreg(esr); + } else { + sysreg = esr_sys64_to_sysreg(esr); + } + + is_read = (esr & ESR_ELx_SYS64_ISS_DIR_MASK) == ESR_ELx_SYS64_ISS_DIR_READ; + + switch (sysreg) { + default: + return 0; + } + + vmcr = __vgic_v3_read_vmcr(); + rt = kvm_vcpu_sys_get_rt(vcpu); + fn(vcpu, vmcr, rt); + + return 1; +} + +#endif diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c index 030248e..fac6e23 100644 --- a/virt/kvm/arm/vgic/vgic-v3.c +++ b/virt/kvm/arm/vgic/vgic-v3.c @@ -429,6 +429,8 @@ out: return ret; } +DEFINE_STATIC_KEY_FALSE(vgic_v3_cpuif_trap); + /** * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT * @node: pointer to the DT node -- 2.7.4