| Message ID | 20200615081954.6233-4-maz@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM/arm64: Enable PtrAuth on non-VHE KVM | expand |
On Mon, Jun 15, 2020 at 09:19:53AM +0100, Marc Zyngier wrote: > Now that the scene is set for enabling PtrAuth on non-VHE, drop > the restrictions preventing userspace from enabling it. > > Signed-off-by: Marc Zyngier <maz@kernel.org> > --- > arch/arm64/kvm/reset.c | 21 ++++++++++----------- > 1 file changed, 10 insertions(+), 11 deletions(-) > > 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; That was easy. Let EL2 use ptrauth and it can save and restore the guest's state and done. Acked-by: Andrew Scull <ascull@google.com>
On Mon, Jun 15, 2020 at 09:19:53AM +0100, Marc Zyngier wrote: > Now that the scene is set for enabling PtrAuth on non-VHE, drop > the restrictions preventing userspace from enabling it. > > Signed-off-by: Marc Zyngier <maz@kernel.org> Other than dropping the `has_vhe()` check this appears to be functionally equivalent and easier to follow, so: Acked-by: Mark Rutland <mark.rutland@arm.com> Mark. > --- > arch/arm64/kvm/reset.c | 21 ++++++++++----------- > 1 file changed, 10 insertions(+), 11 deletions(-) > > 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; > -- > 2.27.0 > > _______________________________________________ > kvmarm mailing list > kvmarm@lists.cs.columbia.edu > https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
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;
Now that the scene is set for enabling PtrAuth on non-VHE, drop the restrictions preventing userspace from enabling it. Signed-off-by: Marc Zyngier <maz@kernel.org> --- arch/arm64/kvm/reset.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-)