On Fri, Nov 13, 2020 at 02:47:04PM +0100, Stefano Garzarella wrote:
> +static void vdpasim_blk_work(struct work_struct *work)
> +{
> +	struct vdpasim *vdpasim = container_of(work, struct vdpasim, work);
> +	u8 status = VIRTIO_BLK_S_OK;
> +	int i;
> +
> +	spin_lock(&vdpasim->lock);
> +
> +	if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
> +		goto out;
> +
> +	for (i = 0; i < VDPASIM_BLK_VQ_NUM; i++) {
> +		struct vdpasim_virtqueue *vq = &vdpasim->vqs[i];
> +
> +		if (!vq->ready)
> +			continue;
> +
> +		while (vringh_getdesc_iotlb(&vq->vring, &vq->iov, &vq->iov,
> +					    &vq->head, GFP_ATOMIC) > 0) {
> +
> +			int write;
> +
> +			vq->iov.i = vq->iov.used - 1;
> +			write = vringh_iov_push_iotlb(&vq->vring, &vq->iov, &status, 1);
> +			if (write <= 0)
> +				break;

We're lucky the guest driver doesn't crash after VIRTIO_BLK_T_GET_ID? :)