Per Intel's SDM, unsupported ENCLS leafs result in a #GP, not a #UD.
SGX1 is a special snowflake as the SGX1 flag is used by the CPU as a
"soft" disable, e.g. if software disables machine check reporting, i.e.
having SGX but not SGX1 is effectively "SGX completely unsupported" and
and thus #UDs.
Fixes: 9798adbc04cf ("KVM: VMX: Frame in ENCLS handler for SGX virtualization")
Cc: Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx>
Cc: Kai Huang <kai.huang@xxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/vmx/sgx.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/arch/x86/kvm/vmx/sgx.c b/arch/x86/kvm/vmx/sgx.c
index f881f6ff6408..1c092ab89c33 100644
--- a/arch/x86/kvm/vmx/sgx.c
+++ b/arch/x86/kvm/vmx/sgx.c
@@ -350,11 +350,12 @@ static int handle_encls_einit(struct kvm_vcpu *vcpu)
static inline bool encls_leaf_enabled_in_guest(struct kvm_vcpu *vcpu, u32 leaf)
{
- if (!enable_sgx || !guest_cpuid_has(vcpu, X86_FEATURE_SGX))
- return false;
-
+ /*
+ * ENCLS #UDs if SGX1 isn't supported, i.e. this point will be reached
+ * if and only if the SGX1 leafs are enabled.
+ */
if (leaf >= ECREATE && leaf <= ETRACK)
- return guest_cpuid_has(vcpu, X86_FEATURE_SGX1);
+ return true;
if (leaf >= EAUG && leaf <= EMODT)
return guest_cpuid_has(vcpu, X86_FEATURE_SGX2);
@@ -373,9 +374,11 @@ int handle_encls(struct kvm_vcpu *vcpu)
{
u32 leaf = (u32)kvm_rax_read(vcpu);
- if (!encls_leaf_enabled_in_guest(vcpu, leaf)) {
+ if (!enable_sgx || !guest_cpuid_has(vcpu, X86_FEATURE_SGX) ||
+ !guest_cpuid_has(vcpu, X86_FEATURE_SGX1)) {
kvm_queue_exception(vcpu, UD_VECTOR);
- } else if (!sgx_enabled_in_guest_bios(vcpu) || !is_paging(vcpu)) {
+ } else if (!encls_leaf_enabled_in_guest(vcpu, leaf) ||
+ !sgx_enabled_in_guest_bios(vcpu) || !is_paging(vcpu)) {
kvm_inject_gp(vcpu, 0);
} else {
if (leaf == ECREATE)
--
2.40.0.348.gf938b09366-goog
