Re: [PATCH 2/3] intel-iommu: fail DEVIOTLB_UNMAP without dt mode

[Laurent Vivier <lvivier@redhat.com>]

On 2/3/23 10:08, Laurent Vivier wrote:
> On 11/29/22 09:10, Jason Wang wrote:
>> Without dt mode, device IOTLB notifier won't work since guest won't
>> send device IOTLB invalidation descriptor in this case. Let's fail
>> early instead of misbehaving silently.
>>
>> Signed-off-by: Jason Wang <jasowang@redhat.com>
>> ---
>>   hw/i386/intel_iommu.c | 8 ++++++++
>>   1 file changed, 8 insertions(+)
>>
>> diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
>> index 9143376677..d025ef2873 100644
>> --- a/hw/i386/intel_iommu.c
>> +++ b/hw/i386/intel_iommu.c
>> @@ -3179,6 +3179,7 @@ static int vtd_iommu_notify_flag_changed(IOMMUMemoryRegion *iommu,
>>   {
>>       VTDAddressSpace *vtd_as = container_of(iommu, VTDAddressSpace, iommu);
>>       IntelIOMMUState *s = vtd_as->iommu_state;
>> +    X86IOMMUState *x86_iommu = X86_IOMMU_DEVICE(s);
>>       /* TODO: add support for VFIO and vhost users */
>>       if (s->snoop_control) {
>> @@ -3193,6 +3194,13 @@ static int vtd_iommu_notify_flag_changed(IOMMUMemoryRegion *iommu,
>>                            PCI_FUNC(vtd_as->devfn));
>>           return -ENOTSUP;
>>       }
>> +    if (!x86_iommu->dt_supported && (new & IOMMU_NOTIFIER_DEVIOTLB_UNMAP)) {
>> +        error_setg_errno(errp, ENOTSUP,
>> +                         "device %02x.%02x.%x requires device IOTLB mode",
>> +                         pci_bus_num(vtd_as->bus), PCI_SLOT(vtd_as->devfn),
>> +                         PCI_FUNC(vtd_as->devfn));
>> +        return -ENOTSUP;
>> +    }
>>       /* Update per-address-space notifier flags */
>>       vtd_as->notifier_flags = new;
> 
> Reviewed-by: Laurent Vivier <lvivier@redhat.com>
> Tested-by: Laurent Vivier <lvivier@redhat.com>
> Buglink: https://bugzilla.redhat.com/2156876

Is this possible to have this patch merged?
It fixes a real problem and it is really trivial.

Thanks,
Laurent