Re: [PATCH] net: lan966x: avoid unregistering netdev on register failure

[Maxime Chevallier <maxime.chevallier@bootlin.com>]

On 26/04/2026 16:27, Myeonghun Pak wrote:
> lan966x_probe_port() stores the newly allocated net_device in the
> port before calling register_netdev(). If register_netdev() fails,
> the probe error path calls lan966x_cleanup_ports(), which sees
> port->dev and calls unregister_netdev() for a device that was never
> registered.
> 
> Destroy the phylink instance created for this port and clear port->dev
> before returning the registration error, matching the existing guard
> used by the common cleanup path.
> 
> Fixes: d28d6d2e37d1 ("net: lan966x: add port module support")
> Co-developed-by: Ijae Kim <ae878000@gmail.com>
> Signed-off-by: Ijae Kim <ae878000@gmail.com>
> Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
> ---
>  drivers/net/ethernet/microchip/lan966x/lan966x_main.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
> index 47752d3fde..22c496f588 100644
> --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
> +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
> @@ -873,6 +873,9 @@ static int lan966x_probe_port(struct lan966x *lan966x, u32 p,
>  	err = register_netdev(dev);
>  	if (err) {
>  		dev_err(lan966x->dev, "register_netdev failed\n");
> +		phylink_destroy(phylink);
> +		port->phylink = NULL;
> +		port->dev = NULL;
>  		return err;
>  	}
>  
> 

Strictly speaking, setting port->dev to NULL should be enough, but IMO
it's a bit cleaner your way as the function cleans everything after itself.

Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com

Maxime