Re: [Qemu-devel] [PATCH] intel_iommu: handle invalid ce for shadow sync

[Peter Xu]

On Mon, Oct 08, 2018 at 02:06:20PM +0800, Peter Xu wrote:
> > > -static int vtd_sync_shadow_page_table(VTDAddressSpace *vtd_as)
> > > -{
> > > -    return vtd_sync_shadow_page_table_range(vtd_as, NULL, 0, UINT64_MAX);
> > > +    return vtd_sync_shadow_page_table_range(vtd_as, &ce, 0, UINT64_MAX);
> > >   }
> > 
> > As has been discussed, this will left addr UINT64_MAX, it's better to have
> > [start, end] instead of (start, range).
> 
> Hmm, this size is inclusive, so we should be fine.  Though I'll take
> your advise to use start/end pair to be clearer.

Sorry it's not...

Actually vtd_page_walk() itself is not inclusive, so we will need to
touch that up if we want to let the whole stack use the [start, end]
inclusive way.  However I would try not to bother with it since after
all page sync operation is per-small-page granularity, so imho missing
the last addr UINT64_MAX is ok (as long as we're covering the last
page, which is UINT64_MAX - PAGE_SIZE + 1).  I'm not sure whether
it'll worth it then to change the whole stack into inclusive way... so
I'll temporarily keep it as is.

Regards,

-- 
Peter Xu