Re: [PATCH v3 29/37] vfio/iommufd: Bypass EEH if iommufd backend

[Cédric Le Goater]

On 10/31/23 03:26, Duan, Zhenzhong wrote:
> > -----Original Message-----
> > From: Cédric Le Goater <clg@redhat.com>
> > Sent: Monday, October 30, 2023 9:57 PM
> > Subject: Re: [PATCH v3 29/37] vfio/iommufd: Bypass EEH if iommufd backend
> >
> > On 10/26/23 12:30, Zhenzhong Duan wrote:
> > > IBM EEH is only supported by legacy backend currently, bypass it
> > > for IOMMUFD backend.
> > >
> > > Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
> > > ---
> > >    hw/ppc/spapr_pci_vfio.c | 4 ++--
> > >    1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/hw/ppc/spapr_pci_vfio.c b/hw/ppc/spapr_pci_vfio.c
> > > index d1d07bec46..a2518838a1 100644
> > > --- a/hw/ppc/spapr_pci_vfio.c
> > > +++ b/hw/ppc/spapr_pci_vfio.c
> > > @@ -93,10 +93,10 @@ static VFIOContainer
> > *vfio_eeh_as_container(AddressSpace *as)
> > >        bcontainer = QLIST_FIRST(&space->containers);
> > >
> > > -    if (QLIST_NEXT(bcontainer, next)) {
> > > +    if (QLIST_NEXT(bcontainer, next) || bcontainer->ops != &vfio_legacy_ops) {
> >
> > It's curious that a test on the VFIOIOMMUOps is needed so deep in
> > the software stack, and spapr should have its own VFIOIOMMUOps, which
> > de facto doesn't support iommufd.
>
> Yes, in this series, spapr shares same ops vfio_legacy_ops, in next series I 
> should
> check with vfio_iommu_spapr_ops.

Well, since PPC doesn't support IOMMUFD it should be tested before or compile
out as suggested on patch 23 "Add iommufd configure option"

Thanks,

C.


> The general vfio-pci device supports iommu property, if we pass a vfio device
> with iommufd backend, I guess we will crash Qemu if there is no check here.
>
> Thanks
> Zhenzhong