Virtualization - Jun 2021 - [PATCH v8 09/10] vduse: Introduce VDUSE - vDPA Device in Userspace

? 2021/6/22 ??4:14, Yongji Xie ??:
> On Tue, Jun 22, 2021 at 3:50 PM Jason Wang <jasowang at redhat.com>
wrote:
>>
>> ? 2021/6/22 ??3:22, Yongji Xie ??:
>>>> We need fix a way to propagate the error to the userspace.
>>>>
>>>> E.g if we want to stop the deivce, we will delay the status
reset until
>>>> we get respose from the userspace?
>>>>
>>> I didn't get how to delay the status reset. And should it be a
DoS
>>> that we want to fix if the userspace doesn't give a response
forever?
>>
>> You're right. So let's make set_status() can fail first, then
propagate
>> its failure via VHOST_VDPA_SET_STATUS.
>>
> OK. So we only need to propagate the failure in the vhost-vdpa case, right?

I think not, we need to deal with the reset for virtio as well:

E.g in register_virtio_devices(), we have:

 ??????? /* We always start by resetting the device, in case a previous
 ???????? * driver messed it up.? This also tests that code path a 
little. */
 ????? dev->config->reset(dev);

We probably need to make reset can fail and then fail the 
register_virtio_device() as well.

Thanks

>
> Thanks,
> Yongji
>