From: Alban Bedel alban.bedel@aerq.com
commit 584b7cfcdc7d6d416a9d6fece9516764bd977d2e upstream.
Multicast entries in the MAC table use the high bits of the MAC address to encode the ports that should get the packets. But this port mask does not work for the CPU port, to receive these packets on the CPU port the MAC_CPU_COPY flag must be set.
Because of this IPv6 was effectively not working because neighbor solicitations were never received. This was not apparent before commit 9403c158 (net: mscc: ocelot: support IPv4, IPv6 and plain Ethernet mdb entries) as the IPv6 entries were broken so all incoming IPv6 multicast was then treated as unknown and flooded on all ports.
To fix this problem rework the ocelot_mact_learn() to set the MAC_CPU_COPY flag when a multicast entry that target the CPU port is added. For this we have to read back the ports endcoded in the pseudo MAC address by the caller. It is not a very nice design but that avoid changing the callers and should make backporting easier.
Signed-off-by: Alban Bedel alban.bedel@aerq.com Fixes: 9403c158b872 ("net: mscc: ocelot: support IPv4, IPv6 and plain Ethernet mdb entries") Link: https://lore.kernel.org/r/20210119140638.203374-1-alban.bedel@aerq.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/net/ethernet/mscc/ocelot.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-)
--- a/drivers/net/ethernet/mscc/ocelot.c +++ b/drivers/net/ethernet/mscc/ocelot.c @@ -60,14 +60,27 @@ int ocelot_mact_learn(struct ocelot *oce const unsigned char mac[ETH_ALEN], unsigned int vid, enum macaccess_entry_type type) { + u32 cmd = ANA_TABLES_MACACCESS_VALID | + ANA_TABLES_MACACCESS_DEST_IDX(port) | + ANA_TABLES_MACACCESS_ENTRYTYPE(type) | + ANA_TABLES_MACACCESS_MAC_TABLE_CMD(MACACCESS_CMD_LEARN); + unsigned int mc_ports; + + /* Set MAC_CPU_COPY if the CPU port is used by a multicast entry */ + if (type == ENTRYTYPE_MACv4) + mc_ports = (mac[1] << 8) | mac[2]; + else if (type == ENTRYTYPE_MACv6) + mc_ports = (mac[0] << 8) | mac[1]; + else + mc_ports = 0; + + if (mc_ports & BIT(ocelot->num_phys_ports)) + cmd |= ANA_TABLES_MACACCESS_MAC_CPU_COPY; + ocelot_mact_select(ocelot, mac, vid);
/* Issue a write command */ - ocelot_write(ocelot, ANA_TABLES_MACACCESS_VALID | - ANA_TABLES_MACACCESS_DEST_IDX(port) | - ANA_TABLES_MACACCESS_ENTRYTYPE(type) | - ANA_TABLES_MACACCESS_MAC_TABLE_CMD(MACACCESS_CMD_LEARN), - ANA_TABLES_MACACCESS); + ocelot_write(ocelot, cmd, ANA_TABLES_MACACCESS);
return ocelot_mact_wait_for_completion(ocelot); }