Re: [PATCH] vdpa/mlx5: Use random MAC address when no nic vport MAC set

["Nelson, Shannon" <shannon.nelson@amd.com>]

On 8/27/2024 9:02 AM, Dragos Tatulea wrote:
> 
> When the vdpa device is configured without a specific MAC
> address, the vport MAC address is used. However, this
> address can be 0 which prevents the driver from properly
> configuring the MPFS and breaks steering.
> 
> The solution is to simply generate a random MAC address
> when no MAC is set on the nic vport.
> 
> Now it's possible to create a vdpa device without a
> MAC address and run qemu with this device without needing
> to configure an explicit MAC address.
> 
> Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
> Reviewed-by: Jiri Pirko <jiri@nvidia.com>
> ---
>   drivers/vdpa/mlx5/net/mlx5_vnet.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index fa78e8288ebb..1c26139d02fe 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -3824,6 +3824,9 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
>                  err = mlx5_query_nic_vport_mac_address(mdev, 0, 0, config->mac);
>                  if (err)
>                          goto err_alloc;
> +
> +               if (is_zero_ether_addr(config->mac))
> +                       eth_random_addr(config->mac);
>          }
> 
>          if (!is_zero_ether_addr(config->mac)) {
> --
> 2.45.1
> 
> 

Reviewed-by: Shannon Nelson <shannon.nelson@amd.com>