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: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 4d11707..e8a35ee 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2120,7 +2120,8 @@
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;