On Fri, Nov 20, 2015 at 03:45:00PM +0200, Victor Kaplansky wrote:
> The VHOST_USER_SET_VRING_ENABLE request is sent for each queue in
> queue-pair separately. So, a queue-pair should be considered
> enabled only when both RX and TX queues are enabled.
>
> The old code caused segfault when last TX queue was enabled.
Since the problem causes segfault, it's important to review this
soon before QEMU 2.5 is out.
Thanks,
-- Victor
>
> Signed-off-by: Victor Kaplansky <victork at redhat.com>
> ---
> lib/librte_vhost/vhost_user/virtio-net-user.c | 14 +++++++++-----
> 1 file changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/lib/librte_vhost/vhost_user/virtio-net-user.c
> b/lib/librte_vhost/vhost_user/virtio-net-user.c
> index d07452a..c06e53e 100644
> --- a/lib/librte_vhost/vhost_user/virtio-net-user.c
> +++ b/lib/librte_vhost/vhost_user/virtio-net-user.c
> @@ -317,21 +317,25 @@ user_set_vring_enable(struct vhost_device_ctx ctx,
> struct vhost_vring_state *state)
> {
> struct virtio_net *dev = get_device(ctx);
> - uint16_t base_idx = state->index;
> + uint16_t idx = state->index;
> + uint16_t base_idx = (idx / VIRTIO_QNUM) * VIRTIO_QNUM;
> int enable = (int)state->num;
> + int qpair_enabled;
>
> RTE_LOG(INFO, VHOST_CONFIG,
> "set queue enable: %d to qp idx: %d\n",
> enable, state->index);
>
> + dev->virtqueue[idx]->enabled = enable;
> + qpair_enabled =
> + dev->virtqueue[base_idx + VIRTIO_RXQ]->enabled &&
> + dev->virtqueue[base_idx + VIRTIO_TXQ]->enabled;
> +
> if (notify_ops->vring_state_changed) {
> notify_ops->vring_state_changed(dev, base_idx / VIRTIO_QNUM,
> - enable);
> + qpair_enabled);
> }
>
> - dev->virtqueue[base_idx + VIRTIO_RXQ]->enabled = enable;
> - dev->virtqueue[base_idx + VIRTIO_TXQ]->enabled = enable;
> -
> return 0;
> }
>
> --
> --Victor
