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Date: Tue, 13 May 2025 16:37:44 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Jakob Unterwurzacher <jakobunt@gmail.com>
Cc: Woojung Huh <woojung.huh@microchip.com>, UNGLinuxDriver@microchip.com,
 Andrew Lunn <andrew@lunn.ch>, Vladimir Oltean <olteanv@gmail.com>, "David
 S. Miller" <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>, Paolo
 Abeni <pabeni@redhat.com>, Simon Horman <horms@kernel.org>, Marek Vasut
 <marex@denx.de>, Tristram Ha <Tristram.Ha@microchip.com>, Florian Fainelli
 <f.fainelli@gmail.com>, jakob.unterwurzacher@cherry.de,
 stable@vger.kernel.org, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH net v2] net: dsa: microchip: linearize skb for
 tail-tagging switches
Message-ID: <20250513163744.20299747@kernel.org>
In-Reply-To: <20250512144416.3697054-1-jakob.unterwurzacher@cherry.de>
References: <20250512144416.3697054-1-jakob.unterwurzacher@cherry.de>
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On Mon, 12 May 2025 16:44:18 +0200 Jakob Unterwurzacher wrote:
>  static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev)
>  {
> +	u8 *tag;
> +
> +	if (skb_linearize(skb))
> +		return NULL;
> +
>  	/* Tag decoding */
> -	u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
> +	tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
>  	unsigned int port = tag[0] & KSZ9477_TAIL_TAG_EG_PORT_M;
>  	unsigned int len = KSZ_EGRESS_TAG_LEN;

Please don't add code before variable declarations.
-- 
pw-bot: cr