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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. To store the data for CAN specific use-cases unused space in CAN skbs is used, namely the inner protocol space for ethernet/IP encapsulation. [1] https://lore.kernel.org/linux-can/20260104074222.29e660ac@kernel.org/ Oliver Hartkopp (5): can: use skb hash instead of private variable in headroom can: move can_iif from private headroom to struct sk_buff can: move frame length from private headroom to struct sk_buff can: remove private skb headroom infrastructure can: gw: use new can_gw_hops variable instead of re-using csum_start drivers/net/can/dev/skb.c | 45 ++++++++++++++++----------------------- include/linux/can/core.h | 1 + include/linux/can/skb.h | 33 ---------------------------- include/linux/skbuff.h | 27 +++++++++++++++++------ net/can/af_can.c | 35 +++++++++++++++++++----------- net/can/bcm.c | 13 ++++------- net/can/gw.c | 25 ++++++---------------- net/can/isotp.c | 18 ++++++---------- net/can/j1939/socket.c | 7 ++---- net/can/j1939/transport.c | 13 ++++------- net/can/raw.c | 14 ++++++------ 11 files changed, 92 insertions(+), 139 deletions(-) -- 2.47.3