Commit f4c63e5d authored by Avi Kivity's avatar Avi Kivity
Browse files

KVM: VMX: Optimize vmx_get_cpl() 



In long mode, vm86 mode is disallowed, so we need not check for
it.  Reading rflags.vm may require a VMREAD, so it is expensive.

Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 6de12732

arch/x86/kvm/vmx.c

+2 −1
Original line number Diff line number Diff line
@@ -2120,7 +2120,8 @@ static int vmx_get_cpl(struct kvm_vcpu *vcpu) 
	if (!is_protmode(vcpu))

		return 0;



	if (kvm_get_rflags(vcpu) & X86_EFLAGS_VM) /* if virtual 8086 */

	if (!is_long_mode(vcpu)

	    && (kvm_get_rflags(vcpu) & X86_EFLAGS_VM)) /* if virtual 8086 */

		return 3;



	return vmcs_read16(GUEST_CS_SELECTOR) & 3;

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