Re: [Xen-devel] why xen use x86_emulation() in page_fault

[Christoph Egger <Christoph.Egger@xxxxxxx>]

On 10/13/11 13:47, Tim Deegan wrote:
> At 21:07 +0800 on 11 Oct (1318367233), cc Luit wrote:
> > > > Why don't you just use EPT/NPT instead of shadow pagetables?  That code
> > > > is a lot simpler and the end result is easier to validate than shadow
> > > > pagetables are.  Is it particularly important to support shadow
> > > pagetables?
> > yeah, we have consider that, and of course the EPT is much more convenient,
> > BTW, do you know is there any simulator that can well support EPT of xen?
> > the shadow page's problem is a little relevent to the selection of
> > simulator~
> There's experimental support in Xen itself for running a hypervisor
> inside a HVM guest.  On AMD, that includes (and indeed requires) NPT in
> the guest hypervisor.
Not quite right: guest hypervisor can use NPT but this is not required.
It may use shadow paging. But an AMD cpu with NPT capability is
required since shadow-on-shadow is not supported.

>  Unfortunately, on Intel it does not include EPT.
> There may be some other simulators that have EPT/NPT - I don't know.
>
> Cheers,
>
> Tim.

--
---to satisfy European Law for business letters:
Advanced Micro Devices GmbH
Einsteinring 24, 85689 Dornach b. Muenchen
Geschaeftsfuehrer: Alberto Bozzo, Andrew Bowd
Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen
Registergericht Muenchen, HRB Nr. 43632


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel