[PATCH 1/2] KVM: SVM: Check for nested vmrun intercept before emulating vmrun

[Joerg Roedel <joerg.roedel@amd.com>]

This patch lets the nested vmrun fail if the L1 hypervisor
has not intercepted vmrun. This fixes the "vmrun intercept
check" unit test.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 arch/x86/kvm/svm.c |   19 +++++++++++++++++++
 1 files changed, 19 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index b44c9cc..083fa88 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -2015,6 +2015,14 @@ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
 	return true;
 }
 
+static bool nested_vmcb_checks(struct vmcb *vmcb)
+{
+	if ((vmcb->control.intercept & (1ULL << INTERCEPT_VMRUN)) == 0)
+		return false;
+
+	return true;
+}
+
 static bool nested_svm_vmrun(struct vcpu_svm *svm)
 {
 	struct vmcb *nested_vmcb;
@@ -2029,6 +2037,17 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
 	if (!nested_vmcb)
 		return false;
 
+	if (!nested_vmcb_checks(nested_vmcb)) {
+		nested_vmcb->control.exit_code    = SVM_EXIT_ERR;
+		nested_vmcb->control.exit_code_hi = 0;
+		nested_vmcb->control.exit_info_1  = 0;
+		nested_vmcb->control.exit_info_2  = 0;
+
+		nested_svm_unmap(page);
+
+		return false;
+	}
+
 	trace_kvm_nested_vmrun(svm->vmcb->save.rip - 3, vmcb_gpa,
 			       nested_vmcb->save.rip,
 			       nested_vmcb->control.int_ctl,
-- 
1.7.0.4