Re: [PATCH v1] vdpa/vdpa_sim: Use the negotiated features when calling vringh_init_iotlb

[Stefano Garzarella]

On Tue, Jul 20, 2021 at 08:25:33AM +0300, Eli Cohen wrote:
> When calling vringh_init_iotlb(), use the negotiated features which
> might be different than the supported features.
>
> Fixes: 2c53d0f64c06f ("vdpasim: vDPA device simulator")
> Signed-off-by: Eli Cohen <elic@xxxxxxxxxx>
> ---
> v0 --> v1:
> Update "Fixes" line
>
> drivers/vdpa/vdpa_sim/vdpa_sim.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> index 14e024de5cbf..89a474c7a096 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> @@ -66,7 +66,7 @@ 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,
> +	vringh_init_iotlb(&vq->vring, vdpasim->features,
> 			  VDPASIM_QUEUE_MAX, false,
> 			  (struct vring_desc *)(uintptr_t)vq->desc_addr,
> 			  (struct vring_avail *)
> @@ -86,7 +86,7 @@ static void vdpasim_vq_reset(struct vdpasim *vdpasim,
> 	vq->device_addr = 0;
> 	vq->cb = NULL;
> 	vq->private = NULL;
> -	vringh_init_iotlb(&vq->vring, vdpasim->dev_attr.supported_features,
> +	vringh_init_iotlb(&vq->vring, vdpasim->features,

vdpasim_vq_reset() is called while resetting the device in 
vdpasim_reset() where we also set `vdpasim->features = 0` after 
resetting the vqs, so maybe it's better to use the supported features 
here, since the negotiated ones are related to the previous instance.

Thanks,
Stefano