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| author | Amit Daniel Kachhap <amit.kachhap@arm.com> | 2019-04-23 06:42:36 +0200 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2019-04-24 16:30:40 +0200 |
| commit | a22fa321d13b0264976cbbc1d22f4c27c41d3642 (patch) | |
| tree | 1f68397998eccf792fa7452d89a00ed6e6350488 /arch/arm64 | |
| parent | KVM: arm/arm64: Context-switch ptrauth registers (diff) | |
| download | linux-a22fa321d13b0264976cbbc1d22f4c27c41d3642.tar.xz linux-a22fa321d13b0264976cbbc1d22f4c27c41d3642.zip | |
KVM: arm64: Add userspace flag to enable pointer authentication
Now that the building blocks of pointer authentication are present, lets
add userspace flags KVM_ARM_VCPU_PTRAUTH_ADDRESS and
KVM_ARM_VCPU_PTRAUTH_GENERIC. These flags will enable pointer
authentication for the KVM guest on a per-vcpu basis through the ioctl
KVM_ARM_VCPU_INIT.
This features will allow the KVM guest to allow the handling of
pointer authentication instructions or to treat them as undefined
if not set.
Necessary documentations are added to reflect the changes done.
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <christoffer.dall@arm.com>
Cc: kvmarm@lists.cs.columbia.edu
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 2 | ||||
| -rw-r--r-- | arch/arm64/include/uapi/asm/kvm.h | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/reset.c | 27 |
3 files changed, 30 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 7eebea7059c6..f772ac2fb3e9 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -49,7 +49,7 @@ #define KVM_MAX_VCPUS VGIC_V3_MAX_CPUS -#define KVM_VCPU_MAX_FEATURES 5 +#define KVM_VCPU_MAX_FEATURES 7 #define KVM_REQ_SLEEP \ KVM_ARCH_REQ_FLAGS(0, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index edd2db8e5160..7b7ac0f6cec9 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -104,6 +104,8 @@ struct kvm_regs { #define KVM_ARM_VCPU_PSCI_0_2 2 /* CPU uses PSCI v0.2 */ #define KVM_ARM_VCPU_PMU_V3 3 /* Support guest PMUv3 */ #define KVM_ARM_VCPU_SVE 4 /* enable SVE for this CPU */ +#define KVM_ARM_VCPU_PTRAUTH_ADDRESS 5 /* VCPU uses address authentication */ +#define KVM_ARM_VCPU_PTRAUTH_GENERIC 6 /* VCPU uses generic authentication */ struct kvm_vcpu_init { __u32 target; diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index 3402543fdcd3..028d0c604652 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -221,6 +221,27 @@ static void kvm_vcpu_reset_sve(struct kvm_vcpu *vcpu) memset(vcpu->arch.sve_state, 0, vcpu_sve_state_size(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. + */ + if (!test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, vcpu->arch.features) || + !test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, vcpu->arch.features)) + return -EINVAL; + + vcpu->arch.flags |= KVM_ARM64_GUEST_HAS_PTRAUTH; + return 0; +} + /** * kvm_reset_vcpu - sets core registers and sys_regs to reset value * @vcpu: The VCPU pointer @@ -261,6 +282,12 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu) kvm_vcpu_reset_sve(vcpu); } + if (test_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, vcpu->arch.features) || + test_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, vcpu->arch.features)) { + if (kvm_vcpu_enable_ptrauth(vcpu)) + goto out; + } + switch (vcpu->arch.target) { default: if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) { |