Re: [Qemu-devel] [RFC-PATCH] Introducing virtio-example device.

[Stefan Hajnoczi]

On Wed, Apr 10, 2019 at 4:45 PM Yoni Bettan <address@hidden> wrote:
> On 4/9/19 4:17 PM, Stefan Hajnoczi wrote:
> > On Mon, Apr 01, 2019 at 02:18:43PM +0300, Yoni Bettan wrote:
> > There are multiple problems with the code, but the larger issue is that
> > this example device is just helping people shoot themselves in the foot
> > more easily.
>
>
> If you can point me to those problem I will be glad so I can update the
> code and understand those problems you are talking about.

Please see Eduardo's reply.  I didn't review much since he already
pointed out many things.

One thing he didn't mention:
+    elem = virtqueue_pop(vq, sizeof(VirtQueueElement));

The return value can be NULL.  Spurious notifications could happen so
the code shouldn't crash when this returns NULL.

I apologize for the critical replies.  What you're doing is valuable.
I think explaining the VIRTIO device model and the order in which
things are done will lead to higher quality devices so I'm making a
lot of noise about it :).

Stefan