Re: [PATCH net] net: dsa: mv88e6xxx: do not leave reserved VLANs

From: Andrew Lunn
Date: Sat Feb 06 2016 - 13:28:04 EST


On Fri, Feb 05, 2016 at 02:07:14PM -0500, Vivien Didelot wrote:
> BRIDGE_VLAN_FILTERING automatically adds a newly bridged port to the
> VLAN with the bridge's default_pvid.
>
> The mv88e6xxx driver currently reserves VLANs 4000+ for unbridged ports
> isolation. When a port joins a bridge, it leaves its reserved VLAN. When
> a port leaves a bridge, it joins again its reserved VLAN.
>
> But if the VLAN filtering is disabled, or if this hardware VLAN is
> already in use, the bridged port ends up with no default VLAN, and the
> communication with the CPU is thus broken.
>
> To fix this, make a port join its reserved VLAN once on setup, never
> leave it, and restore its PVID after another one was eventually used.
>
> Signed-off-by: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>

Tested-by: Andrew Lunn <andrew@xxxxxxx>

Thanks

Andrew


> ---
> drivers/net/dsa/mv88e6xxx.c | 25 ++++++++++---------------
> 1 file changed, 10 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/net/dsa/mv88e6xxx.c b/drivers/net/dsa/mv88e6xxx.c
> index 1cb3d15..4196dd8 100644
> --- a/drivers/net/dsa/mv88e6xxx.c
> +++ b/drivers/net/dsa/mv88e6xxx.c
> @@ -1572,6 +1572,7 @@ int mv88e6xxx_port_vlan_del(struct dsa_switch *ds, int port,
> const struct switchdev_obj_port_vlan *vlan)
> {
> struct mv88e6xxx_priv_state *ps = ds_to_priv(ds);
> + const u16 defpvid = 4000 + ds->index * DSA_MAX_PORTS + port;
> u16 pvid, vid;
> int err = 0;
>
> @@ -1587,7 +1588,8 @@ int mv88e6xxx_port_vlan_del(struct dsa_switch *ds, int port,
> goto unlock;
>
> if (vid == pvid) {
> - err = _mv88e6xxx_port_pvid_set(ds, port, 0);
> + /* restore reserved VLAN ID */
> + err = _mv88e6xxx_port_pvid_set(ds, port, defpvid);
> if (err)
> goto unlock;
> }
> @@ -1879,26 +1881,20 @@ unlock:
>
> int mv88e6xxx_port_bridge_join(struct dsa_switch *ds, int port, u32 members)
> {
> - struct mv88e6xxx_priv_state *ps = ds_to_priv(ds);
> - const u16 pvid = 4000 + ds->index * DSA_MAX_PORTS + port;
> - int err;
> -
> - /* The port joined a bridge, so leave its reserved VLAN */
> - mutex_lock(&ps->smi_mutex);
> - err = _mv88e6xxx_port_vlan_del(ds, port, pvid);
> - if (!err)
> - err = _mv88e6xxx_port_pvid_set(ds, port, 0);
> - mutex_unlock(&ps->smi_mutex);
> - return err;
> + return 0;
> }
>
> int mv88e6xxx_port_bridge_leave(struct dsa_switch *ds, int port, u32 members)
> {
> + return 0;
> +}
> +
> +static int mv88e6xxx_setup_port_default_vlan(struct dsa_switch *ds, int port)
> +{
> struct mv88e6xxx_priv_state *ps = ds_to_priv(ds);
> const u16 pvid = 4000 + ds->index * DSA_MAX_PORTS + port;
> int err;
>
> - /* The port left the bridge, so join its reserved VLAN */
> mutex_lock(&ps->smi_mutex);
> err = _mv88e6xxx_port_vlan_add(ds, port, pvid, true);
> if (!err)
> @@ -2182,8 +2178,7 @@ int mv88e6xxx_setup_ports(struct dsa_switch *ds)
> if (dsa_is_cpu_port(ds, i) || dsa_is_dsa_port(ds, i))
> continue;
>
> - /* setup the unbridged state */
> - ret = mv88e6xxx_port_bridge_leave(ds, i, 0);
> + ret = mv88e6xxx_setup_port_default_vlan(ds, i);
> if (ret < 0)
> return ret;
> }
> --
> 2.7.0
>