Re: [PATCH] vdpa_sim: fix vringh initialization in vdpasim_queue_ready()

[Jason Wang]

On Thu, Nov 10, 2022 at 10:13 PM Stefano Garzarella <sgarzare@xxxxxxxxxx> wrote:
>
> When we initialize vringh, we should pass the features and the
> number of elements in the virtqueue negotiated with the driver,
> otherwise operations with vringh may fail.
>
> This was discovered in a case where the driver sets a number of
> elements in the virtqueue different from the value returned by
> .get_vq_num_max().
>
> In vdpasim_vq_reset() is safe to initialize the vringh with
> default values, since the virtqueue will not be used until
> vdpasim_queue_ready() is called again.
>
> Fixes: 2c53d0f64c06 ("vdpasim: vDPA device simulator")
> Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>

Acked-by: Jason Wang <jasowang@xxxxxxxxxx>

Thanks

> ---
>  drivers/vdpa/vdpa_sim/vdpa_sim.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> index b071f0d842fb..b20689f8fe89 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> @@ -67,8 +67,7 @@ static void vdpasim_queue_ready(struct vdpasim *vdpasim, unsigned int idx)
>  {
>         struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
>
> -       vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features,
> -                         VDPASIM_QUEUE_MAX, false,
> +       vringh_init_iotlb(&vq->vring, vdpasim->features, vq->num, false,
>                           (struct vring_desc *)(uintptr_t)vq->desc_addr,
>                           (struct vring_avail *)
>                           (uintptr_t)vq->driver_addr,
> --
> 2.38.1
>