Re: [PATCH 1/2] vfio/ap: Don't initialize HOST_IOMMU_DEVICE with mdev

[Anthony Krowiak <akrowiak@linux.ibm.com>]

On 7/22/24 5:18 AM, Joao Martins wrote:
> On 22/07/2024 08:07, Zhenzhong Duan wrote:
>> mdevs aren't "physical" devices and when asking for backing IOMMU info,
>> it fails the entire provisioning of the guest. Fix that by setting
>> vbasedev->mdev true so skipping HostIOMMUDevice initialization in the
>> presence of mdevs.
>>
>> Fixes: 930589520128 ("vfio/iommufd: Implement HostIOMMUDeviceClass::realize() handler")
>> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>


I'm at a bit of a loss here. We've been starting guests with AP devices 
being passed through using VFIO for years. Did the fix for

930589520128 precipitate this? Is there a bugzilla or something that 
describes how this problem was encountered?


> Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
>
>> ---
>>   hw/vfio/ap.c | 3 +++
>>   1 file changed, 3 insertions(+)
>>
>> diff --git a/hw/vfio/ap.c b/hw/vfio/ap.c
>> index 0c4354e3e7..391bfb72ca 100644
>> --- a/hw/vfio/ap.c
>> +++ b/hw/vfio/ap.c
>> @@ -230,6 +230,9 @@ static void vfio_ap_instance_init(Object *obj)
>>        */
>>       vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_AP, &vfio_ap_ops,
>>                        DEVICE(vapdev), true);
>> +
>> +    /* AP device is mdev type device */
>> +    vbasedev->mdev = true;
>>   }
>>   
>>   #ifdef CONFIG_IOMMUFD