On 2020/6/23 下午3:00, Eugenio Perez Martin wrote:

On Tue, Jun 23, 2020 at 4:51 AM Jason Wang [off-list ref] wrote:

quoted

On 2020/6/23 上午12:00, Michael S. Tsirkin wrote:

quoted

On Wed, Jun 17, 2020 at 11:19:26AM +0800, Jason Wang wrote:

quoted

On 2020/6/11 下午7:34, Michael S. Tsirkin wrote:

quoted

    static void vhost_vq_free_iovecs(struct vhost_virtqueue *vq)
    {
     kfree(vq->descs);

@@ -394,6 +400,9 @@ static long vhost_dev_alloc_iovecs(struct vhost_dev *dev)
     for (i = 0; i < dev->nvqs; ++i) {
             vq = dev->vqs[i];
             vq->max_descs = dev->iov_limit;
+           if (vhost_vq_num_batch_descs(vq) < 0) {
+                   return -EINVAL;
+           }

This check breaks vdpa which set iov_limit to zero. Consider iov_limit is
meaningless to vDPA, I wonder we can skip the test when device doesn't use
worker.

Thanks

It doesn't need iovecs at all, right?

-- MST

Yes, so we may choose to bypass the iovecs as well.

Thanks

I think that the kmalloc_array returns ZERO_SIZE_PTR for all of them
in that case, so I didn't bother to skip the kmalloc_array parts.
Would you prefer to skip them all and let them NULL? Or have I
misunderstood what you mean?

I'm ok with either approach, but my understanding is that Michael wants 
to skip them all.

Thanks

Thanks!