----- liran.alon@xxxxxxxxxx wrote:
> ----- sean.j.christopherson@xxxxxxxxx wrote:
>
> > On Tue, 2018-05-22 at 08:50 -0700, Jim Mattson wrote:
> > > While we're on the subject, is there any need for L0 to allocate
> a
> > > vpid02 in the common case, where nested EPT is enabled?
> > >
> > > Per section 28.3.2 of the SDM, volume 3, when EPT is enabled,
> > combined
> > > mappings in the TLB are tagged by {VPID, PCID, EP4TA}. With
> nested
> > > EPT, vmcs02 and vmcs01 do not share an EP4TA. Therefore, I think
> it
> > > suffices to simply copy the VPID field from vmcs12 to vmcs02 in
> > this
> > > case.
> >
> > VPID handling in general looks like it could use a good once-over,
> > e.g. vpid02 allocation can be delayed until prepare_vmcs02_full(),
> > we never re-attempt VPID allocation in the (extremely unlikely)
> > case that there are no available VPIDs at vmx_create_vcpu(), and
> > load_vmcs12_host_state() explicitly flushes the TLB when VPID is
> > enabled because it has obsolete code that assumes L1 and L2 always
> > share a VPID.
>
> Agree with all the above.
> As a starting point, I think we should apply this current series as it
> at-least
> handle the load_vmcs12_host_state() issue. :)
>
> Will also add handling for the rest of these issues in my upcoming
> series.
> Thanks for explicitly pointing these out.
>
> >
Paolo / Radim:
Do you agree with me that it makes sense to first apply this series as a first step?
Or do you want me to resend these patches as part of a bigger series that will fix the extra issues we discussed here?
