[PATCH v11 43/43] KVM: arm64: nv: Allow userspace to request KVM_ARM_VCPU_NESTED_VIRT

[Marc Zyngier]

Since we're (almost) feature complete, let's allow userspace to
request KVM_ARM_VCPU_NESTED_VIRT by bumping the KVM_VCPU_MAX_FEATURES
up. We also now advertise the feature to userspace with a new capability.

It's going to be great...

Signed-off-by: Marc Zyngier <maz at kernel.org>
---
 arch/arm64/include/asm/kvm_host.h | 2 +-
 arch/arm64/kvm/arm.c              | 3 +++
 include/uapi/linux/kvm.h          | 1 +
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index f96fc5a3dde0..74dcae972d77 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -39,7 +39,7 @@
 
 #define KVM_MAX_VCPUS VGIC_V3_MAX_CPUS
 
-#define KVM_VCPU_MAX_FEATURES 7
+#define KVM_VCPU_MAX_FEATURES 8
 #define KVM_VCPU_VALID_FEATURES	(BIT(KVM_VCPU_MAX_FEATURES) - 1)
 
 #define KVM_REQ_SLEEP \
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index d684a2af3406..2ce02d9ef11d 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -289,6 +289,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_ARM_EL1_32BIT:
 		r = cpus_have_final_cap(ARM64_HAS_32BIT_EL1);
 		break;
+	case KVM_CAP_ARM_EL2:
+		r = cpus_have_final_cap(ARM64_HAS_NESTED_VIRT);
+		break;
 	case KVM_CAP_GUEST_DEBUG_HW_BPS:
 		r = get_num_brps();
 		break;
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 211b86de35ac..6cd6a677163a 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1201,6 +1201,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE 228
 #define KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES 229
 #define KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES 230
+#define KVM_CAP_ARM_EL2 231
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
-- 
2.39.2