From aff7cce0d337f5468470d614ef83a507dcf4c93f Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 11 Jun 2020 13:20:28 +0100 Subject: KVM: arm64: Allow PtrAuth to be enabled from userspace on non-VHE systems Now that the scene is set for enabling PtrAuth on non-VHE, drop the restrictions preventing userspace from enabling it. Acked-by: Andrew Scull Acked-by: Mark Rutland Signed-off-by: Marc Zyngier --- arch/arm64/kvm/reset.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) (limited to 'arch/arm64/kvm/reset.c') diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index d3b209023727..2a929789fe2e 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -42,6 +42,11 @@ static u32 kvm_ipa_limit; #define VCPU_RESET_PSTATE_SVC (PSR_AA32_MODE_SVC | PSR_AA32_A_BIT | \ PSR_AA32_I_BIT | PSR_AA32_F_BIT) +static bool system_has_full_ptr_auth(void) +{ + return system_supports_address_auth() && system_supports_generic_auth(); +} + /** * kvm_arch_vm_ioctl_check_extension * @@ -80,8 +85,7 @@ int kvm_arch_vm_ioctl_check_extension(struct kvm *kvm, long ext) break; case KVM_CAP_ARM_PTRAUTH_ADDRESS: case KVM_CAP_ARM_PTRAUTH_GENERIC: - r = has_vhe() && system_supports_address_auth() && - system_supports_generic_auth(); + r = system_has_full_ptr_auth(); break; default: r = 0; @@ -205,19 +209,14 @@ static void kvm_vcpu_reset_sve(struct kvm_vcpu *vcpu) static int kvm_vcpu_enable_ptrauth(struct kvm_vcpu *vcpu) { - /* Support ptrauth only if the system supports these capabilities. */ - if (!has_vhe()) - return -EINVAL; - - if (!system_supports_address_auth() || - !system_supports_generic_auth()) - return -EINVAL; /* * For now make sure that both address/generic pointer authentication - * features are requested by the userspace together. + * features are requested by the userspace together and the system + * supports these capabilities. */ if (!test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, vcpu->arch.features) || - !test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, vcpu->arch.features)) + !test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, vcpu->arch.features) || + !system_has_full_ptr_auth()) return -EINVAL; vcpu->arch.flags |= KVM_ARM64_GUEST_HAS_PTRAUTH; -- cgit v1.2.3