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Date: Fri, 7 Jun 2024 14:26:28 +0300
From: Vladimir Oltean <olteanv@gmail.com>
To: Martin Schiller <ms@dev.tdt.de>
Cc: martin.blumenstingl@googlemail.com, hauke@hauke-m.de, andrew@lunn.ch,
	f.fainelli@gmail.com, davem@davemloft.net, edumazet@google.com,
	kuba@kernel.org, pabeni@redhat.com, robh@kernel.org,
	krzk+dt@kernel.org, conor+dt@kernel.org, netdev@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next 09/13] net: dsa: lantiq_gswip: Forbid
 gswip_add_single_port_br on the CPU port
Message-ID: <20240607112628.igcf6ytqe6wbmbq5@skbuf>
References: <20240606085234.565551-1-ms@dev.tdt.de>
 <20240606085234.565551-10-ms@dev.tdt.de>
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On Thu, Jun 06, 2024 at 10:52:30AM +0200, Martin Schiller wrote:
> From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> 
> Calling gswip_add_single_port_br() with the CPU port would be a bug
> because then only the CPU port could talk to itself. Add the CPU port to
> the validation at the beginning of gswip_add_single_port_br().
> 
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> ---
>  drivers/net/dsa/lantiq_gswip.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c
> index ee8296d5b901..d2195271ffe9 100644
> --- a/drivers/net/dsa/lantiq_gswip.c
> +++ b/drivers/net/dsa/lantiq_gswip.c
> @@ -657,7 +657,7 @@ static int gswip_add_single_port_br(struct gswip_priv *priv, int port, bool add)
>  	unsigned int max_ports = priv->hw_info->max_ports;
>  	int err;
>  
> -	if (port >= max_ports) {
> +	if (port >= max_ports || dsa_is_cpu_port(priv->ds, port)) {
>  		dev_err(priv->dev, "single port for %i supported\n", port);
>  		return -EIO;
>  	}
> -- 
> 2.39.2
> 

Isn't the new check effectively dead code?