Re: [V11 PATCH 3/4] pvh dom0: Add and remove foreign pages

["Jan Beulich" <JBeulich@suse.com>]

>>> On 07.05.14 at 03:12, <mukesh.rathor@oracle.com> wrote:
> On Tue, 06 May 2014 08:51:24 +0100
> "Jan Beulich" <JBeulich@suse.com> wrote:
> 
>> >>> On 06.05.14 at 03:21, <mukesh.rathor@oracle.com> wrote:
>> > "Jan Beulich" <JBeulich@suse.com> wrote:
>> >> >>> On 02.05.14 at 03:55, <mukesh.rathor@oracle.com> wrote:
>> >> > @@ -444,6 +451,10 @@ int p2m_alloc_table(struct p2m_domain *p2m)
>> >> >      return rc;
>> >> >  }
>> >> >  
>> >> > +/*
>> >> > + * pvh fixme: when adding support for pvh non-hardware domains,
>> >> > this path must
>> >> > + * cleanup any foreign p2m types (release refcnts on them).
>> >> > + */
>> >> 
>> >> And I wonder whether you shouldn't enforce this by disallowing non-
>> >> hardware domains to create foreign mappings.
>> > 
>> > Hmm... Tim wanted the enforcement. That will ensure the cleanup is
>> > implemented without falling thru the cracks.
>> 
>> I'm confused - aren't you stating that Tim requested the same I did?
>> Or else, what "enforcement" are you referring to?
> 
> Yes, Tim requested enforcement which I added in p2m_add_foreign():
> 
> +    /*
> +     * pvh fixme: until support is added to p2m teardown code to cleanup any
> +     * foreign entries, limit this to hardware domain only.
> +     */
> +    if ( !is_hardware_domain(tdom) )
> +        return -EPERM;
> 
> Thus, non-hardware domains can't map foreign types. Not sure if there's
> anything worth enforcing in p2m_teardown with above.

I must have overlooked this - this is exactly what I was after. Sorry
for the noise.

Jan