Re: [PATCH 1/3] i386: Add missing "vmx-ept-wb" feature name

[Paolo Bonzini]

On 02/02/21 01:18, Eduardo Habkost wrote:
> On Tue, Feb 02, 2021 at 12:28:38AM +0100, Paolo Bonzini wrote:
> > Il mar 2 feb 2021, 00:05 Eduardo Habkost <ehabkost@redhat.com> ha scritto:
> >
> > > On Mon, Feb 01, 2021 at 11:59:48PM +0100, Paolo Bonzini wrote:
> > > > Il lun 1 feb 2021, 23:54 Eduardo Habkost <ehabkost@redhat.com> ha
> > > scritto:
> > > > > Not having a feature name in feature_word_info breaks error
> > > > > reporting and query-cpu-model-expansion.  Add the missing feature
> > > > > name to feature_word_info[FEAT_VMX_EPT_VPID_CAPS].feat_names[14].
> > > > This is intentional, because there's no way that any hypervisor can run
> > > if
> > > > this feature is disabled.
> > >
> > > If leaving the feature without name enables some desirable
> > > behavior, that's by accident and not by design.  Which part of
> > > the existing behavior is intentional?
> >
> > Not being able to disable it.
>
> We can make it a hard dependency of vmx, then.  We shouldn't
> leave it without a name, though.

The feature is already added to the MSRs unconditionally in 
kvm_msr_entry_add_vmx.  I think we can just remove it from the models 
instead.

Paolo