Re: [PATCH v11 1/2] vhost-vdpa: Skip the range check while MR is IOMMU

[Cindy Lu]

On Thu, 8 Dec 2022 at 15:42, Jason Wang <jasowang@redhat.com> wrote:
>
> On Wed, Nov 30, 2022 at 1:33 PM Cindy Lu <lulu@redhat.com> wrote:
> >
> > Skip the check in vhost_vdpa_listener_skipped_section() while
> > MR is IOMMU, Move this check to  vhost_vdpa_iommu_map_notify()
> >
> > Signed-off-by: Cindy Lu <lulu@redhat.com>
> > ---
> >  hw/virtio/vhost-vdpa.c | 21 ++++++++++++++-------
> >  1 file changed, 14 insertions(+), 7 deletions(-)
> >
> > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
> > index 3ff9ce3501..f0e9963d19 100644
> > --- a/hw/virtio/vhost-vdpa.c
> > +++ b/hw/virtio/vhost-vdpa.c
> > @@ -60,15 +60,22 @@ static bool 
> > vhost_vdpa_listener_skipped_section(MemoryRegionSection *section,
> >                       iova_min, section->offset_within_address_space);
> >          return true;
> >      }
> > +    /*
> > +     * While using vIOMMU, Sometimes the section will be larger than 
> > iova_max
> > +     * but the memory that  actually mapping is smaller, So skip the check
> > +     * here. Will add the check in vhost_vdpa_iommu_map_notify,
> > +     *There is the real size that maps to the kernel
> > +     */
> >
>
> I suggest squashing this into the next patch since we haven't
> implemented vhost_vdpa_iommu_map_notify() yet.
>
> Thanks
>
Sure, will do
Thanks
Cindy
> > -    llend = vhost_vdpa_section_end(section);
> > -    if (int128_gt(llend, int128_make64(iova_max))) {
> > -        error_report("RAM section out of device range (max=0x%" PRIx64
> > -                     ", end addr=0x%" PRIx64 ")",
> > -                     iova_max, int128_get64(llend));
> > -        return true;
> > +    if (!memory_region_is_iommu(section->mr)) {
> > +        llend = vhost_vdpa_section_end(section);
> > +        if (int128_gt(llend, int128_make64(iova_max))) {
> > +            error_report("RAM section out of device range (max=0x%" PRIx64
> > +                         ", end addr=0x%" PRIx64 ")",
> > +                         iova_max, int128_get64(llend));
> > +            return true;
> > +        }
> >      }
> > -
> >      return false;
> >  }
> >
> > --
> > 2.34.3
> >
>