vdpa/mlx5: preserve CVQ vringh index

mlx5_vdpa does not preserve userland's view of vring base for the control
queue in the following sequence:

ioctl VHOST_SET_VRING_BASE
ioctl VHOST_VDPA_SET_STATUS VIRTIO_CONFIG_S_DRIVER_OK
  mlx5_vdpa_set_status()
    setup_cvq_vring()
      vringh_init_iotlb()
        vringh_init_kern()
          vrh->last_avail_idx = 0;
ioctl VHOST_GET_VRING_BASE

To fix, restore the value of cvq->vring.last_avail_idx after calling
vringh_init_iotlb.

Fixes: 5262912ef3 ("vdpa/mlx5: Add support for control VQ and MAC setting")

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <1699014387-194368-1-git-send-email-steven.sistare@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Steve Sistare 2023-11-03 05:26:27 -07:00 committed by Michael S. Tsirkin
parent 2cc14f52ae
commit 480b3e7372

View file

@ -2815,13 +2815,18 @@ static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev)
struct mlx5_control_vq *cvq = &mvdev->cvq;
int err = 0;
if (mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ))
if (mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)) {
u16 idx = cvq->vring.last_avail_idx;
err = vringh_init_iotlb(&cvq->vring, mvdev->actual_features,
MLX5_CVQ_MAX_ENT, false,
(struct vring_desc *)(uintptr_t)cvq->desc_addr,
(struct vring_avail *)(uintptr_t)cvq->driver_addr,
(struct vring_used *)(uintptr_t)cvq->device_addr);
if (!err)
cvq->vring.last_avail_idx = cvq->vring.last_used_idx = idx;
}
return err;
}