From: Sascha Bischoff Date: Thu, 19 Mar 2026 15:56:59 +0000 (+0000) Subject: KVM: arm64: gic-v5: Create and initialise vgic_v5 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=f4d37c7c35769579c51aa5fe00161c690b89811d;p=thirdparty%2Fkernel%2Flinux.git KVM: arm64: gic-v5: Create and initialise vgic_v5 Update kvm_vgic_create to create a vgic_v5 device. When creating a vgic, FEAT_GCIE in the ID_AA64PFR2 is only exposed to vgic_v5-based guests, and is hidden otherwise. GIC in ~ID_AA64PFR0_EL1 is never exposed for a vgic_v5 guest. When initialising a vgic_v5, skip kvm_vgic_dist_init as GICv5 doesn't support one. The current vgic_v5 implementation only supports PPIs, so no SPIs are initialised either. The current vgic_v5 support doesn't extend to nested guests. Therefore, the init of vgic_v5 for a nested guest is failed in vgic_v5_init. As the current vgic_v5 doesn't require any resources to be mapped, vgic_v5_map_resources is simply used to check that the vgic has indeed been initialised. Again, this will change as more GICv5 support is merged in. Signed-off-by: Sascha Bischoff Reviewed-by: Jonathan Cameron Link: https://patch.msgid.link/20260319154937.3619520-29-sascha.bischoff@arm.com Signed-off-by: Marc Zyngier --- diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c index e0366e8c144d5..75185651ff64c 100644 --- a/arch/arm64/kvm/vgic/vgic-init.c +++ b/arch/arm64/kvm/vgic/vgic-init.c @@ -66,7 +66,7 @@ static int vgic_allocate_private_irqs_locked(struct kvm_vcpu *vcpu, u32 type); * or through the generic KVM_CREATE_DEVICE API ioctl. * irqchip_in_kernel() tells you if this function succeeded or not. * @kvm: kvm struct pointer - * @type: KVM_DEV_TYPE_ARM_VGIC_V[23] + * @type: KVM_DEV_TYPE_ARM_VGIC_V[235] */ int kvm_vgic_create(struct kvm *kvm, u32 type) { @@ -131,8 +131,11 @@ int kvm_vgic_create(struct kvm *kvm, u32 type) if (type == KVM_DEV_TYPE_ARM_VGIC_V2) kvm->max_vcpus = VGIC_V2_MAX_CPUS; - else + else if (type == KVM_DEV_TYPE_ARM_VGIC_V3) kvm->max_vcpus = VGIC_V3_MAX_CPUS; + else if (type == KVM_DEV_TYPE_ARM_VGIC_V5) + kvm->max_vcpus = min(VGIC_V5_MAX_CPUS, + kvm_vgic_global_state.max_gic_vcpus); if (atomic_read(&kvm->online_vcpus) > kvm->max_vcpus) { ret = -E2BIG; @@ -426,22 +429,28 @@ int vgic_init(struct kvm *kvm) if (kvm->created_vcpus != atomic_read(&kvm->online_vcpus)) return -EBUSY; - /* freeze the number of spis */ - if (!dist->nr_spis) - dist->nr_spis = VGIC_NR_IRQS_LEGACY - VGIC_NR_PRIVATE_IRQS; + if (!vgic_is_v5(kvm)) { + /* freeze the number of spis */ + if (!dist->nr_spis) + dist->nr_spis = VGIC_NR_IRQS_LEGACY - VGIC_NR_PRIVATE_IRQS; - ret = kvm_vgic_dist_init(kvm, dist->nr_spis); - if (ret) - goto out; + ret = kvm_vgic_dist_init(kvm, dist->nr_spis); + if (ret) + return ret; - /* - * Ensure vPEs are allocated if direct IRQ injection (e.g. vSGIs, - * vLPIs) is supported. - */ - if (vgic_supports_direct_irqs(kvm)) { - ret = vgic_v4_init(kvm); + /* + * Ensure vPEs are allocated if direct IRQ injection (e.g. vSGIs, + * vLPIs) is supported. + */ + if (vgic_supports_direct_irqs(kvm)) { + ret = vgic_v4_init(kvm); + if (ret) + return ret; + } + } else { + ret = vgic_v5_init(kvm); if (ret) - goto out; + return ret; } kvm_for_each_vcpu(idx, vcpu, kvm) @@ -449,12 +458,12 @@ int vgic_init(struct kvm *kvm) ret = kvm_vgic_setup_default_irq_routing(kvm); if (ret) - goto out; + return ret; vgic_debug_init(kvm); dist->initialized = true; -out: - return ret; + + return 0; } static void kvm_vgic_dist_destroy(struct kvm *kvm) @@ -598,6 +607,7 @@ int vgic_lazy_init(struct kvm *kvm) int kvm_vgic_map_resources(struct kvm *kvm) { struct vgic_dist *dist = &kvm->arch.vgic; + bool needs_dist = true; enum vgic_type type; gpa_t dist_base; int ret = 0; @@ -616,12 +626,16 @@ int kvm_vgic_map_resources(struct kvm *kvm) if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2) { ret = vgic_v2_map_resources(kvm); type = VGIC_V2; - } else { + } else if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) { ret = vgic_v3_map_resources(kvm); type = VGIC_V3; + } else { + ret = vgic_v5_map_resources(kvm); + type = VGIC_V5; + needs_dist = false; } - if (ret) + if (ret || !needs_dist) goto out; dist_base = dist->vgic_dist_base; diff --git a/arch/arm64/kvm/vgic/vgic-v5.c b/arch/arm64/kvm/vgic/vgic-v5.c index b84324f0a3114..14e1fad913f06 100644 --- a/arch/arm64/kvm/vgic/vgic-v5.c +++ b/arch/arm64/kvm/vgic/vgic-v5.c @@ -87,6 +87,32 @@ int vgic_v5_probe(const struct gic_kvm_info *info) return 0; } +int vgic_v5_init(struct kvm *kvm) +{ + struct kvm_vcpu *vcpu; + unsigned long idx; + + if (vgic_initialized(kvm)) + return 0; + + kvm_for_each_vcpu(idx, vcpu, kvm) { + if (vcpu_has_nv(vcpu)) { + kvm_err("Nested GICv5 VMs are currently unsupported\n"); + return -EINVAL; + } + } + + return 0; +} + +int vgic_v5_map_resources(struct kvm *kvm) +{ + if (!vgic_initialized(kvm)) + return -EBUSY; + + return 0; +} + int vgic_v5_finalize_ppi_state(struct kvm *kvm) { struct kvm_vcpu *vcpu0; diff --git a/arch/arm64/kvm/vgic/vgic.h b/arch/arm64/kvm/vgic/vgic.h index 8f15f7472458e..0f1986fcd7d0a 100644 --- a/arch/arm64/kvm/vgic/vgic.h +++ b/arch/arm64/kvm/vgic/vgic.h @@ -364,6 +364,8 @@ void vgic_debug_init(struct kvm *kvm); void vgic_debug_destroy(struct kvm *kvm); int vgic_v5_probe(const struct gic_kvm_info *info); +int vgic_v5_init(struct kvm *kvm); +int vgic_v5_map_resources(struct kvm *kvm); void vgic_v5_set_ppi_ops(struct kvm_vcpu *vcpu, u32 vintid); bool vgic_v5_has_pending_ppi(struct kvm_vcpu *vcpu); void vgic_v5_flush_ppi_state(struct kvm_vcpu *vcpu); diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index a28cf765f3eb5..a5ddccf7ef3b0 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -21,6 +21,7 @@ #include #include +#define VGIC_V5_MAX_CPUS 512 #define VGIC_V3_MAX_CPUS 512 #define VGIC_V2_MAX_CPUS 8 #define VGIC_NR_IRQS_LEGACY 256