Re: [Qemu-devel] 答复: Re: [PATCH] vhost: don't set vring call fd to -1 invhost_virtqueue_start for vhost-user

[Jason Wang]

On 2017年08月21日 11:28, address@hidden wrote:
>   if (!vdev->use_guest_notifier_mask) {
>
>          /* TODO: check and handle errors. */
>
>          vhost_virtqueue_mask(dev, vdev, idx, false)
>
>          ---------- set right  callfd
>
>      }
>
>
>
>
>      if (k->query_guest_notifiers &&
>
>          k->query_guest_notifiers(qbus->parent) &&
>
>          virtio_queue_vector(vdev, idx) == VIRTIO_NO_VECTOR) {
>
>          file.fd = -1
>
>          r = dev->vhost_ops->vhost_set_vring_call(dev, &file)
>
> -----------set call fd to -1
>
>          if (r) {
>
>              goto fail_vector
>
>          }
>
>      }
>
>   So   the callfd of  ovs+dpdk in host  is -1.  it  can't be able  to interact 
> with the guest.

The queue does not even an vector, so it won't generate any interrupt. 
Why callfd is still needed?

Thanks