On Friday, 2021-07-30 at 22:17:02 GMT, Sean Christopherson wrote:

On Thu, Jul 29, 2021, David Edmondson wrote:

quoted

When passing the failing address and size out to user space, SGX must
ensure not to trample on the earlier fields of the emulation_failure
sub-union of struct kvm_run.

Signed-off-by: David Edmondson <redacted>
---
 arch/x86/kvm/vmx/sgx.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/vmx/sgx.c b/arch/x86/kvm/vmx/sgx.c
index 6693ebdc0770..63fb93163383 100644
--- a/arch/x86/kvm/vmx/sgx.c
+++ b/arch/x86/kvm/vmx/sgx.c

@@ -53,11 +53,9 @@ static int sgx_get_encls_gva(struct kvm_vcpu *vcpu, unsigned long offset,
 static void sgx_handle_emulation_failure(struct kvm_vcpu *vcpu, u64 addr,
 					 unsigned int size)
 {
-	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
-	vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
-	vcpu->run->internal.ndata = 2;
-	vcpu->run->internal.data[0] = addr;
-	vcpu->run->internal.data[1] = size;
+	uint64_t data[2] = { addr, size };
+
+	kvm_prepare_emulation_failure_exit(vcpu, false, data, sizeof(data));

Assuming we go with my suggestion to have kvm_prepare_emulation_failure_exit()
capture the exit reason/info, it's probably worth converting all the
KVM_EXIT_INTERNAL_ERROR paths in sgx.c, even though the others don't clobber flags.

Okay.