Re: [PATCH 06/11] kvm: Change kvm_iommu_map_pages to map large pages

Marcelo Tosatti
2010-02-01T19:30:17Z

On Mon, Feb 01, 2010 at 03:18:04PM +0100, Joerg Roedel wrote:
> On Fri, Jan 29, 2010 at 10:32:33AM +0100, Joerg Roedel wrote:
> > On Thu, Jan 28, 2010 at 08:24:55PM -0200, Marcelo Tosatti wrote:
> > > On Thu, Jan 28, 2010 at 12:37:57PM +0100, Joerg Roedel wrote:
> > > > +static pfn_t kvm_pin_pages(struct kvm *kvm, struct kvm_memory_slot *slot,
> > > > + gfn_t gfn, unsigned long size)
> > > > +{
> > > > + gfn_t end_gfn;
> > > > + pfn_t pfn;
> > > > +
> > > > + pfn = gfn_to_pfn_memslot(kvm, slot, gfn);
> > >
> > > If gfn_to_pfn_memslot returns pfn of bad_page, you might create a
> > > large iommu translation for it?
> >
> > Right. But that was broken even before this patch. Anyway, I will fix
> > it.
> >
> > > > + /* Map into IO address space */
> > > > + r = iommu_map(domain, gfn_to_gpa(gfn), pfn_to_hpa(pfn),
> > > > + get_order(page_size), flags);
> > > > +
> > > > + gfn += page_size >> PAGE_SHIFT;
> > >
> > > Should increase gfn after checking for failure, otherwise wrong
> > > npages is passed to kvm_iommu_put_pages.
> >
> > True. Will fix that too.
>
> Here is the updated patch (also updated in the iommu/largepage branch of
> my tree). Does it look ok?

Yes, addresses the concern.