[PATCH v4 4/9] KVM: nVMX: check GUEST_IA32_PERF_GLOBAL_CTRL on VM-Entry

[Oliver Upton <oupton@xxxxxxxxxx>]

Add condition to nested_vmx_check_guest_state() to check the validity of
GUEST_IA32_PERF_GLOBAL_CTRL. Per Intel's SDM Vol 3 26.3.1.1:

  If the "load IA32_PERF_GLOBAL_CTRL" VM-entry 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@xxxxxxxxxx>
Co-developed-by: Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>
Signed-off-by: Krish Sadhukhan <krish.sadhukhan@xxxxxxxxxx>
Signed-off-by: Oliver Upton <oupton@xxxxxxxxxx>
Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>
Reviewed-by: Peter Shier <pshier@xxxxxxxxxx>
---
 arch/x86/kvm/vmx/nested.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 9ba90b38d74b..6c3aa3bcede3 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -10,6 +10,7 @@
 #include "hyperv.h"
 #include "mmu.h"
 #include "nested.h"
+#include "pmu.h"
 #include "trace.h"
 #include "x86.h"
 
@@ -2732,6 +2733,7 @@ static int nested_vmx_check_guest_state(struct kvm_vcpu *vcpu,
 					u32 *exit_qual)
 {
 	bool ia32e;
+	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
 
 	*exit_qual = ENTRY_FAIL_DEFAULT;
 
@@ -2748,6 +2750,11 @@ static int nested_vmx_check_guest_state(struct kvm_vcpu *vcpu,
 		return -EINVAL;
 	}
 
+	if (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL &&
+	    !kvm_is_valid_perf_global_ctrl(pmu,
+					   vmcs12->guest_ia32_perf_global_ctrl))
+		return -EINVAL;
+
 	/*
 	 * If the load IA32_EFER VM-entry control is 1, the following checks
 	 * are performed on the field for the IA32_EFER MSR:
-- 
2.23.0.187.g17f5b7556c-goog