Re: [PATCH v8 15/17] vfio-user: handle device interrupts

[Jag Raman]

> On Apr 25, 2022, at 6:27 AM, Stefan Hajnoczi <stefanha@redhat.com> wrote:
> 
> On Tue, Apr 19, 2022 at 04:44:20PM -0400, Jagannathan Raman wrote:
>> +static MSIMessage vfu_object_msi_prepare_msg(PCIDevice *pci_dev,
>> +                                             unsigned int vector)
>> +{
>> +    MSIMessage msg;
>> +
>> +    msg.address = 0;
>> +    msg.data = vector;
>> +
>> +    return msg;
>> +}
>> +
>> +static void vfu_object_msi_trigger(PCIDevice *pci_dev, MSIMessage msg)
>> +{
>> +    vfu_ctx_t *vfu_ctx = pci_dev->irq_opaque;
>> +
>> +    vfu_irq_trigger(vfu_ctx, msg.data);
>> +}
> 
> Why did you switch to vfu_object_msi_prepare_msg() +
> vfu_object_msi_trigger() in this revision?

We previously did not do this switch because the server didn’t get updates
to the MSIx table & PBA.

The latest client version (which is not part of this series) forwards accesses
to the MSIx table & PBA over to the server. It also reads the PBA set by the
server. These change make it possible for the server to make this switch.

Thank you!
--
Jag

> 
> Stefan