Re: [PATCH net-next v2 1/2] net: lan743x: add "message level" module parameter

[Jacob Keller]

On 5/27/2026 11:18 AM, David Thompson wrote:
> The lan743x driver currently hardcodes the initial value of the msg_enable
> parameter during probe(), and uses this value for netdev message logging.
> Instead, the driver should provide a "message level" module parameter to
> allow users to configure the logging level at load time.
> 
> Signed-off-by: David Thompson <davthompson@xxxxxxxxxx>
> ---
> v2:
> - new patch added in v2
> ---
>  drivers/net/ethernet/microchip/lan743x_main.c | 15 ++++++++++++---
>  1 file changed, 12 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
> index f3332417162e..793633cced19 100644
> --- a/drivers/net/ethernet/microchip/lan743x_main.c
> +++ b/drivers/net/ethernet/microchip/lan743x_main.c
> @@ -28,6 +28,17 @@
>  
>  #define RFE_RD_FIFO_TH_3_DWORDS	0x3
>  
> +#define LAN743X_DEF_MSG_ENABLE \
> +	(NETIF_MSG_DRV      | \
> +	 NETIF_MSG_PROBE    | \
> +	 NETIF_MSG_LINK     | \
> +	 NETIF_MSG_IFUP     | \
> +	 NETIF_MSG_IFDOWN   | \
> +	 NETIF_MSG_TX_QUEUED)
> +static int lan743x_msg_enable = -1;
> +module_param(lan743x_msg_enable, int, 0);
> +MODULE_PARM_DESC(lan743x_msg_enable, "Debug message level");
> +

I guess many drivers have msg_enable parameters already so  this isn't
"new", but the netdev maintainers have frowned on adding any module
parameters for years.

You could handle this by just always using the dynamic debug capability
instead of the netdev msg_enable infrastructure, but the driver does
already use this infrastructure heavily, so I guess it makes sense to
expose it and allow changing the settings during early init prior to
when the netdevice is available to userspace..

Since this is a relatively common module parameter and not something
"new" or trying to do anything other than aid in debugging I suppose
this is likely acceptable.

Thanks,
Jake

>  static bool pci11x1x_is_a0(struct lan743x_adapter *adapter)
>  {
>  	u32 dev_rev = adapter->csr.id_rev & ID_REV_CHIP_REV_MASK_;
> @@ -3661,9 +3672,7 @@ static int lan743x_pcidev_probe(struct pci_dev *pdev,
>  	pci_set_drvdata(pdev, netdev);
>  	adapter = netdev_priv(netdev);
>  	adapter->netdev = netdev;
> -	adapter->msg_enable = NETIF_MSG_DRV | NETIF_MSG_PROBE |
> -			      NETIF_MSG_LINK | NETIF_MSG_IFUP |
> -			      NETIF_MSG_IFDOWN | NETIF_MSG_TX_QUEUED;
> +	adapter->msg_enable = netif_msg_init(lan743x_msg_enable, LAN743X_DEF_MSG_ENABLE);
>  	netdev->max_mtu = LAN743X_MAX_FRAME_SIZE;
>  
>  	of_get_mac_address(pdev->dev.of_node, adapter->mac_address);