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

["Cédric Le Goater" <clg@redhat.com>]

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
>