net: dsa: sja1105: always enable the INCL_SRCPT option
commit b4638af8 upstream. Link-local traffic on bridged SJA1105 ports is sometimes tagged by the hardware with source port information (when the port is under a VLAN aware bridge). The tag_8021q source port identification has become more loose ("imprecise") and will report a plausible rather than exact bridge port, when under a bridge (be it VLAN-aware or VLAN-unaware). But link-local traffic always needs to know the precise source port. Modify the driver logic (and therefore: the tagging protocol itself) to always include the source port information with link-local packets, regardless of whether the port is standalone, under a VLAN-aware or VLAN-unaware bridge. This makes it possible for the tagging driver to give priority to that information over the tag_8021q VLAN header. The big drawback with INCL_SRCPT is that it makes it impossible to distinguish between an original MAC DA of 01:80:C2:XX:YY:ZZ and 01:80:C2:AA:BB:ZZ, because the tagger just patches MAC DA bytes 3 and 4 with zeroes. Only if PTP RX timestamping is enabled, the switch will generate a META follow-up frame containing the RX timestamp and the original bytes 3 and 4 of the MAC DA. Those will be used to patch up the original packet. Nonetheless, in the absence of PTP RX timestamping, we have to live with this limitation, since it is more important to have the more precise source port information for link-local traffic. Fixes: d7f9787a ("net: dsa: tag_8021q: add support for imprecise RX based on the VBID") Fixes: 91495f21 ("net: dsa: tag_8021q: replace the SVL bridging with VLAN-unaware IVL bridging") Signed-off-by:Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by:
Simon Horman <simon.horman@corigine.com> Signed-off-by:
Paolo Abeni <pabeni@redhat.com> Stable-dep-of: c1ae02d8 ("net: dsa: tag_sja1105: always prefer source port information from INCL_SRCPT") Signed-off-by:
Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
parent
21c0fe2d
Please register or sign in to comment