RE: [EXTERNAL] [PATCH net v2] net: marvell: prestera: initialize err in prestera_port_sfp_bind

[Elad Nachman]

> 
> 
> From: Ruoyu Wang <ruoyuw560@xxxxxxxxx>
> Sent: Wednesday, June 17, 2026 10:32 PM
> To: Taras Chornyi <taras.chornyi@xxxxxxxxxxx>; Andrew Lunn <andrew+netdev@xxxxxxx>; David S. Miller <davem@xxxxxxxxxxxxx>; Eric Dumazet <edumazet@xxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>; Paolo Abeni <pabeni@xxxxxxxxxx>; Russell King <linux@xxxxxxxxxxxxxxx>; Oleksandr Mazur <oleksandr.mazur@xxxxxxxxxxx>; Yevhen Orlov <yevhen.orlov@xxxxxxxxxxx>; netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: [EXTERNAL] [PATCH net v2] net: marvell: prestera: initialize err in prestera_port_sfp_bind
> 
> prestera_port_sfp_bind() returns err after walking the ports node. If no child node matches the port's front-panel id, err is never assigned. Initialize err to 0 because absence of a matching optional port device tree node is not an error. In
> 
> prestera_port_sfp_bind() returns err after walking the ports node. If no
> child node matches the port's front-panel id, err is never assigned.
> 
> Initialize err to 0 because absence of a matching optional port device
> tree node is not an error. In that case no phylink is created and port
> creation should continue with port->phy_link left NULL. Errors from
> malformed matched nodes and phylink_create() still propagate.
> 
> Fixes: 52323ef75414 ("net: marvell: prestera: add phylink support")
> Signed-off-by: Ruoyu Wang <mailto:ruoyuw560@xxxxxxxxx>
> ---
> v2:
> - Add net tree target to the subject.
> - Explain why the no-match path returns 0 instead of -ENODEV.
> 
>  drivers/net/ethernet/marvell/prestera/prestera_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/marvell/prestera/prestera_main.c b/drivers/net/ethernet/marvell/prestera/prestera_main.c
> index 41e19e9ad28d4..a82e7a8029851 100644
> --- a/drivers/net/ethernet/marvell/prestera/prestera_main.c
> +++ b/drivers/net/ethernet/marvell/prestera/prestera_main.c
> @@ -373,7 +373,7 @@ static int prestera_port_sfp_bind(struct prestera_port *port)
>  	struct device_node *ports, *node;
>  	struct fwnode_handle *fwnode;
>  	struct phylink *phy_link;
> -	int err;
> +	int err = 0;
> 
>  	if (!sw->np)
>  		return 0;
> --
> 2.51.0
> 

prestera_port_sfp_bind() iterates only SFP ports.
Although all currently existing switch boards have at least one SFP uplink port,
In theory a manufacturer might produce a switch board without any SFP ports,
which will unnecessarily fail this function call, so for resolving this case indeed
err should be initialized to zero to make this function return 0 and not an error.

Acked-by: Elad Nachman <enachman@xxxxxxxxxxx>