Re: [PATCH v3 18/38] mlxbf-tmfifo: sparse tags for config access

From: Andy Shevchenko
Date: Wed Aug 05 2020 - 16:06:22 EST


On Wed, Aug 5, 2020 at 4:44 PM Michael S. Tsirkin <mst@xxxxxxxxxx> wrote:
>
> mlxbf-tmfifo accesses config space using native types -
> which works for it since the legacy virtio native types.
>
> This will break if it ever needs to support modern virtio,
> so with new tags previously introduced for virtio net config,
> sparse now warns for this in drivers.
>
> Since this is a legacy only device, fix it up using
> virtio_legacy_is_little_endian for now.
>
> No functional changes.
>

Acked-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>

> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
> Acked-by: Cornelia Huck <cohuck@xxxxxxxxxx>
> ---
> drivers/platform/mellanox/mlxbf-tmfifo.c | 13 ++++++++++---
> 1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/platform/mellanox/mlxbf-tmfifo.c b/drivers/platform/mellanox/mlxbf-tmfifo.c
> index 5739a9669b29..bbc4e71a16ff 100644
> --- a/drivers/platform/mellanox/mlxbf-tmfifo.c
> +++ b/drivers/platform/mellanox/mlxbf-tmfifo.c
> @@ -625,7 +625,10 @@ static void mlxbf_tmfifo_rxtx_header(struct mlxbf_tmfifo_vring *vring,
> vdev_id = VIRTIO_ID_NET;
> hdr_len = sizeof(struct virtio_net_hdr);
> config = &fifo->vdev[vdev_id]->config.net;
> - if (ntohs(hdr.len) > config->mtu +
> + /* A legacy-only interface for now. */
> + if (ntohs(hdr.len) >
> + __virtio16_to_cpu(virtio_legacy_is_little_endian(),
> + config->mtu) +
> MLXBF_TMFIFO_NET_L2_OVERHEAD)
> return;
> } else {
> @@ -1231,8 +1234,12 @@ static int mlxbf_tmfifo_probe(struct platform_device *pdev)
>
> /* Create the network vdev. */
> memset(&net_config, 0, sizeof(net_config));
> - net_config.mtu = ETH_DATA_LEN;
> - net_config.status = VIRTIO_NET_S_LINK_UP;
> +
> + /* A legacy-only interface for now. */
> + net_config.mtu = __cpu_to_virtio16(virtio_legacy_is_little_endian(),
> + ETH_DATA_LEN);
> + net_config.status = __cpu_to_virtio16(virtio_legacy_is_little_endian(),
> + VIRTIO_NET_S_LINK_UP);
> mlxbf_tmfifo_get_cfg_mac(net_config.mac);
> rc = mlxbf_tmfifo_create_vdev(dev, fifo, VIRTIO_ID_NET,
> MLXBF_TMFIFO_NET_FEATURES, &net_config,
> --
> MST
>


--
With Best Regards,
Andy Shevchenko