On 18.10.2017 03:42, Wanpeng Li wrote: > From: Wanpeng Li <wanpeng.li@xxxxxxxxxxx> > > I can use vmxcap tool to observe "EPTP Switching yes" even if EPT is not > exposed to L1. > > EPT switching is advertised unconditionally since it is emulated, however, > it can be treated as an extended feature for EPT and it should not be > advertised if EPT itself is not exposed. This patch fixes it. > > Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> > Cc: Radim Krčmář <rkrcmar@xxxxxxxxxx> > Cc: Jim Mattson <jmattson@xxxxxxxxxx> > Signed-off-by: Wanpeng Li <wanpeng.li@xxxxxxxxxxx> > --- > v2 -> v3: > * it is legal for the IA32_VMX_VMFUNC MSR to report all-zero > v1 -> v2: > * don't advertise "EPT VM Functions" in secondary processor-based VM-execution > controls if we don't actually support any VM Functions. > > arch/x86/kvm/vmx.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index c460b0b..3644540 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -2842,8 +2842,9 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx) > * Advertise EPTP switching unconditionally > * since we emulate it > */ > - vmx->nested.nested_vmx_vmfunc_controls = > - VMX_VMFUNC_EPTP_SWITCHING; > + if (enable_ept) > + vmx->nested.nested_vmx_vmfunc_controls = > + VMX_VMFUNC_EPTP_SWITCHING; > } > > /* > I think we talked about how that cannot happen. But you observe it, so it seems to happen :) Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> -- Thanks, David
