Re: [Xen-devel] [PATCH V2 6/7]: PVH: balloon and grant changes

[Ian Campbell <Ian.Campbell@citrix.com>]

On Wed, 2012-10-17 at 01:09 +0100, Mukesh Rathor wrote:
> > >  		gsv.version = 1;
> > >  	else
> > >  		gsv.version = 2;
> > > @@ -1083,12 +1088,24 @@ static void gnttab_request_version(void)
> > >  int gnttab_resume(void)
> > >  {
> > >  	unsigned int max_nr_gframes;
> > > +	char *kmsg = "Failed to kmalloc pages for pv in hvm grant
> > > frames\n"; 
> > >  	gnttab_request_version();
> > >  	max_nr_gframes = gnttab_max_grant_frames();
> > >  	if (max_nr_gframes < nr_grant_frames)
> > >  		return -ENOSYS;
> > >  
> > > +	/* PVH note: xen will free existing kmalloc'd mfn in
> > > +	 * XENMEM_add_to_physmap */
> > 
> > It doesn't leak it?
> > We should consider using xenballoon_alloc_pages here.
> 
> Well, it's a one time allocation of a dozen (iirc) pages, that are 
> returned back to dom heap.

>  We could use xenballoon, but for that we
> need to create vma first so we get the contigous VA,
>  then map each pte
> since xenballoon_ doesn't return contigous pages, and then populate
> physmap. I'm gonna punt it to phase II.  Lets get some working baseline
> in asap.

That's fair enough.