[PATCH v2 5/8] KVM: nVMX: Check HOST_IA32_PERF_GLOBAL_CTRL on VM-entry

[Oliver Upton <oupton@google.com>]

Add a consistency check on nested vm-entry for host's
IA32_PERF_GLOBAL_CTRL from vmcs12. Per Intel's SDM Vol 3 26.2.2:

  If the "load IA32_PERF_GLOBAL_CTRL"
  VM-exit control is 1, bits reserved in the IA32_PERF_GLOBAL_CTRL
  MSR must be 0 in the field for that register"

Suggested-by: Jim Mattson <jmattson@google.com>
Co-developed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Oliver Upton <oupton@google.com>
---
 arch/x86/kvm/vmx/nested.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 6c3aa3bcede3..e2baa9ca562f 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -2636,6 +2636,7 @@ static int nested_vmx_check_host_state(struct kvm_vcpu *vcpu,
 				       struct vmcs12 *vmcs12)
 {
 	bool ia32e;
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 
 	if (!nested_host_cr0_valid(vcpu, vmcs12->host_cr0) ||
 	    !nested_host_cr4_valid(vcpu, vmcs12->host_cr4) ||
@@ -2650,6 +2651,11 @@ static int nested_vmx_check_host_state(struct kvm_vcpu *vcpu,
 	    !kvm_pat_valid(vmcs12->host_ia32_pat))
 		return -EINVAL;
 
+	if (vmcs12->vm_exit_controls & VM_EXIT_LOAD_IA32_PERF_GLOBAL_CTRL &&
+	    !kvm_is_valid_perf_global_ctrl(pmu,
+					   vmcs12->host_ia32_perf_global_ctrl))
+		return -EINVAL;
+
 	ia32e = (vmcs12->vm_exit_controls &
 		 VM_EXIT_HOST_ADDR_SPACE_SIZE) != 0;
 
-- 
2.23.0.187.g17f5b7556c-goog