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).
Reviewed-by: Eric Auger <[email protected]> Signed-off-by: Marc Zyngier <[email protected]> --- 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 b18e852d27e8..4572a9b560fa 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 aede1658aeda..dfd8ca16601b 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -350,6 +350,20 @@ int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu) } } + 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 ef718586321c..39b9fc4dc65d 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -285,6 +285,7 @@ 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 990d9d1e85d0..943bf11252d9 100644 --- a/virt/kvm/arm/hyp/vgic-v3-sr.c +++ b/virt/kvm/arm/hyp/vgic-v3-sr.c @@ -19,6 +19,7 @@ #include <linux/irqchip/arm-gic-v3.h> #include <linux/kvm_host.h> +#include <asm/kvm_emulate.h> #include <asm/kvm_hyp.h> #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 6fe3f003636a..88d9bd9bf468 100644 --- a/virt/kvm/arm/vgic/vgic-v3.c +++ b/virt/kvm/arm/vgic/vgic-v3.c @@ -410,6 +410,8 @@ int vgic_v3_map_resources(struct kvm *kvm) 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 -- 2.11.0 _______________________________________________ kvmarm mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
