Re: [PATCH 13/17] PVH xen: p2m related changes.

[Mukesh Rathor <mukesh.rathor@oracle.com>]

On Thu, 25 Apr 2013 12:28:13 +0100
Tim Deegan <tim@xen.org> wrote:

> At 14:26 -0700 on 23 Apr (1366727162), Mukesh Rathor wrote:
> > In this patch, I introduce  a new type p2m_map_foreign for pages
> > that a dom0 maps from foreign domains its creating. Also, add
> > set_foreign_p2m_entry() to map p2m_map_foreign type pages. Other
> > misc changes related to p2m.
> 
> You haven't addressed my comments from v2:
> http://lists.xen.org/archives/html/xen-devel/2013-03/msg01895.html
> 
> In particular this:
> 
> >      /* Track the highest gfn for which we have ever had a valid
> > mapping */
> > -    if ( p2mt != p2m_invalid &&
> > +    if ( p2mt != p2m_invalid && p2mt != p2m_mmio_dm &&
> >           (gfn + (1UL << order) - 1 > p2m->max_mapped_pfn) )
> >          p2m->max_mapped_pfn = gfn + (1UL << order) - 1;
> 
> seems like a big change to be hiding away in a 'p2m related changes'
> patch without a good explanation of what you're doing and why.
> 
> Tim.

Remember:
http://lists.xen.org/archives/html/xen-devel/2012-03/msg02456.html

Ok, I'll comment saying "because Tim says so", just kidding..... 

Ok how about comment like this:

/*
 * PVH maps the entire mmio 1-1. Hence we must adjust the max_mapped_pfn
 * to account for that. Such mfns are p2m_mmio_direct and !mfn_valid.
 */

I can't think of better way of saying it, so please feel free to send 
better version if you can.

thanks,
Mukesh