Re: [PATCH net-next v8 1/8] hsr: Add header_ops::parse_protocol

[Sebastian Andrzej Siewior <bigeasy@linutronix.de>]

On 2026-10-06 14:31:12 [+0000], netdev-bot+sashiko@kernel.org wrote:
> [Severity: Low]
> This isn't a bug, but could the commit message also say why this is
> needed?
> 
> The description is correct. In net/packet/af_packet.c,
> packet_parse_headers() does:
> 
>     if ((!skb->protocol || skb->protocol == htons(ETH_P_ALL)) &&
>         sock->type == SOCK_RAW)
>         skb->protocol = dev_parse_header_protocol(skb);
> 
>     skb_probe_transport_header(skb);
> 
> As far as I can tell, the reason for the change is the later patch in
> this series, "hsr: Add a magic header for sending PTP packets". That
> patch adds this check in hsr_dev_xmit():
> 
>     if (skb->protocol == htons(ETH_P_1588)) {
> 
> A SOCK_RAW sender bound to protocol 0 or ETH_P_ALL only passes that
> check because of this callback. Should the message mention this
> dependency?

Yes. It is missing for the HSR case so I added it in order to make the
mentioned check work.

> Users of the hsr device will also see some changes. They now get the
> real ethertype instead of 0 in these places:
> 
>   - skb_probe_transport_header()
>   - the VLAN network header adjustment in packet_parse_headers()
>   - tc/clsact protocol matching on the hsr device
>   - taps on the hsr device
> 
> There is also no Fixes: tag. Could the message say whether this is a
> standalone fix or a prerequisite for the PTP work, so backporters can
> decide whether they need it?

I'm not aware of anything broken so it is just a prerequisite for this
series. Therefore no Fixes tag.

Sebastian