Commit 15fe455d authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: nVMX: Add consistency check for TPR_THRESHOLD[31:4]!=0 without VID 

Add a missing consistency check on the TPR Threshold.  Per the SDM

  If the "use TPR shadow" VM-execution control is 1 and the "virtual-
  interrupt delivery" VM-execution control is 0, bits 31:4 of the TPR
  threshold VM-execution control field must be 0.

Note, nested_vmx_check_tpr_shadow_controls() bails early if "use TPR
shadow" is 0.

Link: https://lore.kernel.org/r/20250919005955.1366256-6-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 2f723a86

arch/x86/kvm/vmx/nested.c

+3 −0
Original line number Diff line number Diff line
@@ -555,6 +555,9 @@ static int nested_vmx_check_tpr_shadow_controls(struct kvm_vcpu *vcpu, 
	if (CC(!page_address_valid(vcpu, vmcs12->virtual_apic_page_addr)))

		return -EINVAL;



	if (CC(!nested_cpu_has_vid(vmcs12) && vmcs12->tpr_threshold >> 4))

		return -EINVAL;



	return 0;

}