Re: [PATCH v2 net-next 08/10] net: dsa: sja1105: Make sja1105_is_link_local not match meta frames

From: Vladimir Oltean
Date: Sun Jun 02 2019 - 18:04:28 EST


On Mon, 3 Jun 2019 at 00:40, Vladimir Oltean <olteanv@xxxxxxxxx> wrote:
>
> Although meta frames are configured to be sent at SJA1105_META_DMAC
> (01-80-C2-00-00-0E) which is a multicast MAC address that would also be
> trapped by the switch to the CPU, were it to receive it on a front-panel
> port, meta frames are conceptually not link-local frames, they only
> carry their RX timestamps.
>
> The choice of sending meta frames at a multicast DMAC is a pragmatic
> one, to avoid installing an extra entry to the DSA master port's
> multicast MAC filter.
>
> Signed-off-by: Vladimir Oltean <olteanv@xxxxxxxxx>
> ---
> Changes in v2:
>
> Patch is new.
>
> include/linux/dsa/sja1105.h | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/include/linux/dsa/sja1105.h b/include/linux/dsa/sja1105.h
> index f3237afed35a..d64e56d6c521 100644
> --- a/include/linux/dsa/sja1105.h
> +++ b/include/linux/dsa/sja1105.h
> @@ -31,6 +31,8 @@ static inline bool sja1105_is_link_local(const struct sk_buff *skb)
> const struct ethhdr *hdr = eth_hdr(skb);
> u64 dmac = ether_addr_to_u64(hdr->h_dest);
>
> + if (ntohs(hdr->h_proto) == ETH_P_SJA1105_META)
> + return false;
> if ((dmac & SJA1105_LINKLOCAL_FILTER_A_MASK) ==
> SJA1105_LINKLOCAL_FILTER_A)
> return true;
> --
> 2.17.1
>

Please be aware that this patch is misplaced and should be moved after
the current 09/10 (doesn't compile as 08/10).
I'll bundle this change in v3 with the other feedback I'll hopefully get.

Thanks!
-Vladimir