Re: [PATCH 1/4] KVM: MMU: fix permission_fault()

[Xiao Guangrong]

On 03/30/2016 02:36 PM, Paolo Bonzini wrote:
> On 30/03/2016 03:56, Xiao Guangrong wrote:
> > > x86/access.flat is currently using the "other" definition, i.e., PFEC.PK
> > > is only set if W=1 or CR0.WP=0 && PFEC.U=0 or PFEC.W=0.  Can you use it
> > > (with ept=1 of course) to check what the processor is doing?
> >
> > Sure.
> >
> > And ept=1 is hard to trigger MMU issue, i am enabling PKEY on shadow
> > MMU, let's see what will happen. ;)
>
> No, don't do that!
>
> ept=1 lets you test what the processor does.  It means you cannot test
> permission_fault(), but what we want here is just reverse engineering
> the microcode.  ept=1 lets you do exactly that.

Yes, i got this point. Huaitong will do the test once the machine gets
free.