Re: [PATCH v2 2/4] vfio/pci: Add an architecture specific error handler

["Cédric Le Goater" <clg@redhat.com>]

On 9/3/25 18:49, Farhan Ali wrote:
> 
> On 9/1/2025 4:28 AM, Cédric Le Goater wrote:
>> On 8/25/25 23:24, Farhan Ali wrote:
>>> Provide a architecture specific error handling callback, that can be used
>>> by platforms to handle PCI errors for passthrough devices.
>>>
>>> Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
>>> ---
>>>   hw/vfio/pci.c | 5 +++++
>>>   hw/vfio/pci.h | 1 +
>>>   2 files changed, 6 insertions(+)
>>>
>>> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
>>> index 07257d0fa0..3c71d19306 100644
>>> --- a/hw/vfio/pci.c
>>> +++ b/hw/vfio/pci.c
>>> @@ -3026,6 +3026,11 @@ static void vfio_err_notifier_handler(void *opaque)
>>>           return;
>>>       }
>>>   +    if (vdev->arch_err_handler) {
>>> +        vdev->arch_err_handler(vdev);
>>
>>
>> I am not sure that the "architecture specific error handling"
>> will be implemented this way but we need to check for potential
>> errors.
> 
> Thanks for reviewing, do you have any suggestions on how to implement the architecture/device specific error handling?

The nature of VFIOPCIDevice is special, it's both a PCIDevice and
a VFIODevice and it's difficult to use QOM to customize some of
its behavior with device class handlers. I don't see a better
way for now.

I would drop the 'arch_' prefix from the name.


>> So, please make the handler return a bool and add an extra
>> 'Error **' parameter.
>>
>>
> Sure, I can change that. Are you suggesting the change to bool return for the handler to report any failures in the handler (through errp)?

yes. The error reported before the vm_stop() in vfio_err_notifier_handler()
should be updated too.

Thanks,

C.