[PATCH 4.4 296/312] net: dsa: mv88e6xxx: fix port VLAN maps

From: Greg Kroah-Hartman
Date: Fri May 08 2020 - 08:48:28 EST


From: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>

commit be1faa92e83b1252d9200c59d8c98aab44463f1e upstream.

Currently the port based VLAN maps should be configured to allow every
port to egress frames on all other ports, except themselves.

The debugfs interface shows that they are misconfigured. For instance, a
7-port switch has the following content in the related register 0x06:

GLOBAL GLOBAL2 SERDES 0 1 2 3 4 5 6
...
6: 1fa4 1f0f 4 7f 7e 7d 7c 7b 7a 79
...

This means that port 3 is allowed to talk to port 2-6, but cannot talk
to ports 0 and 1. With this fix, port 3 can correctly talk to all ports
except 3 itself:

GLOBAL GLOBAL2 SERDES 0 1 2 3 4 5 6
...
6: 1fa4 1f0f 4 7e 7d 7b 77 6f 5f 3f
...

Fixes: ede8098d0fef ("net: dsa: mv88e6xxx: bridges do not need an FID")
Reported-by: Kevin Smith <kevin.smith@xxxxxxxxxxxxxxx>
Signed-off-by: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Tested-by: Kevin Smith <kevin.smith@xxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/dsa/mv88e6xxx.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/net/dsa/mv88e6xxx.c
+++ b/drivers/net/dsa/mv88e6xxx.c
@@ -2150,7 +2150,8 @@ static int mv88e6xxx_setup_port(struct d
* database, and allow every port to egress frames on all other ports.
*/
reg = BIT(ps->num_ports) - 1; /* all ports */
- ret = _mv88e6xxx_port_vlan_map_set(ds, port, reg & ~port);
+ reg &= ~BIT(port); /* except itself */
+ ret = _mv88e6xxx_port_vlan_map_set(ds, port, reg);
if (ret)
goto abort;