From: Jakub Kicinski <kuba@kernel.org>
To: Oliver Hartkopp via B4 Relay <devnull+socketcan.hartkopp.net@kernel.org>
Cc: socketcan@hartkopp.net, netdev@vger.kernel.org,
linux-can@vger.kernel.org, Marc Kleine-Budde <mkl@pengutronix.de>
Subject: Re: [PATCH net-next v4 0/6] move CAN skb headroom content to skb extensions
Date: Wed, 28 Jan 2026 17:41:37 -0800 [thread overview]
Message-ID: <20260128174137.65929694@kernel.org> (raw)
In-Reply-To: <20260128-can_skb_ext-v1-0-330f60fd5d7e@hartkopp.net>
On Wed, 28 Jan 2026 23:43:39 +0100 Oliver Hartkopp via B4 Relay wrote:
> CAN bus related skbuffs (ETH_P_CAN/ETH_P_CANFD/ETH_P_CANXL) simply contain
> CAN frame structs for CAN CC/FD/XL of skb->len length at skb->data. Those
> CAN skbs do not have network/mac/transport headers nor other such
> references for encapsulated protocols like ethernet/IP protocols.
>
> To store data for CAN specific use-cases all CAN bus related skbuffs are
> created with a 16 byte private skb headroom (struct can_skb_priv). Using
> the skb headroom and accessing skb->head for this private data led to
> several problems in the past likely due to "The struct can_skb_priv
> business is highly unconventional for the networking stack." [1]
>
> This patch set aims to remove the unconventional skb headroom usage for CAN
> bus related skbuffs and use the common skb extensions instead.
If you're targeting netdev trees please comply with our community
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prev parent reply other threads:[~2026-01-29 1:41 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-28 22:43 [PATCH net-next v4 0/6] move CAN skb headroom content to skb extensions Oliver Hartkopp via B4 Relay
2026-01-28 22:43 ` [PATCH net-next V4 1/6] can: use skb hash instead of private variable in headroom Oliver Hartkopp via B4 Relay
2026-01-28 22:43 ` [PATCH net-next V4 2/6] can: add CAN skb extension infrastructure Oliver Hartkopp via B4 Relay
2026-01-28 22:43 ` [PATCH net-next V4 3/6] can: move ifindex to CAN skb extensions Oliver Hartkopp via B4 Relay
2026-01-28 22:43 ` [PATCH net-next V4 4/6] can: move frame_len " Oliver Hartkopp via B4 Relay
2026-01-28 22:43 ` [PATCH net-next V4 5/6] can: remove private CAN skb headroom infrastructure Oliver Hartkopp via B4 Relay
2026-01-28 22:43 ` [PATCH net-next V4 6/6] can: gw: use can_gw_hops instead of sk_buff::csum_start Oliver Hartkopp via B4 Relay
2026-01-29 1:41 ` Jakub Kicinski [this message]
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