Re: [Qemu-devel] [PATCH v2 2/2] intel_iommu: handle invalid ce for shadow sync

[Peter Xu <peterx@redhat.com>]

On Tue, Oct 09, 2018 at 09:27:15AM +0200, Auger Eric wrote:

[...]

> > @@ -1056,12 +1058,28 @@ static int vtd_sync_shadow_page_table(VTDAddressSpace *vtd_as)
> >  {
> >      int ret;
> >      VTDContextEntry ce;
> > +    IOMMUNotifier *n;
> >  
> >      ret = vtd_dev_to_context_entry(vtd_as->iommu_state,
> >                                     pci_bus_num(vtd_as->bus),
> >                                     vtd_as->devfn, &ce);
> >      if (ret) {
> > -        return ret;
> > +        if (ret == -VTD_FR_CONTEXT_ENTRY_P) {
> > +            /*
> > +             * It's a valid scenario to have a context entry that is
> > +             * not present.  For example, when a device is removed
> > +             * from an existing domain then the context entry will be
> > +             * zeroed by the guest before it was put into another
> > +             * domain.  When this happens, instead of synchronizing
> > +             * the shadow pages we should invalidate all existing
> > +             * mappings and notify the backends.
> > +             */
> > +            IOMMU_NOTIFIER_FOREACH(n, &vtd_as->iommu) {
> > +                vtd_address_space_unmap(vtd_as, n);
> > +            }
> don't you want to return here also in this case?

Yes... a stupid mistake!

I'll repost.  Thank you,

-- 
Peter Xu