On Sun, Mar 21, 2021 at 00:59, Vladimir Oltean <olte...@gmail.com> wrote:
> From: Vladimir Oltean <vladimir.olt...@nxp.com>
>
> DSA is aware of switches with global VLAN filtering since the blamed
> commit, but it makes a bad decision when multiple bridges are spanning
> the same switch:
>
> ip link add br0 type bridge vlan_filtering 1
> ip link add br1 type bridge vlan_filtering 1
> ip link set swp2 master br0
> ip link set swp3 master br0
> ip link set swp4 master br1
> ip link set swp5 master br1
> ip link set swp5 nomaster
> ip link set swp4 nomaster
> [138665.939930] sja1105 spi0.1: port 3: dsa_core: VLAN filtering is a global
> setting
> [138665.947514] DSA: failed to notify DSA_NOTIFIER_BRIDGE_LEAVE
>
> When all ports leave br1, DSA blindly attempts to disable VLAN filtering
> on the switch, ignoring the fact that br0 still exists and is VLAN-aware
> too. It fails while doing that.
>
> This patch checks whether any port exists at all and is under a
> VLAN-aware bridge.
>
> Fixes: d371b7c92d19 ("net: dsa: Unset vlan_filtering when ports leave the
> bridge")
> Signed-off-by: Vladimir Oltean <vladimir.olt...@nxp.com>
> Tested-by: Florian Fainelli <f.faine...@gmail.com>
> Reviewed-by: Florian Fainelli <f.faine...@gmail.com>
> ---
> net/dsa/switch.c | 15 +++++++++------
> 1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/net/dsa/switch.c b/net/dsa/switch.c
> index 4b5da89dc27a..32963276452f 100644
> --- a/net/dsa/switch.c
> +++ b/net/dsa/switch.c
> @@ -107,7 +107,7 @@ static int dsa_switch_bridge_leave(struct dsa_switch *ds,
> bool unset_vlan_filtering = br_vlan_enabled(info->br);
> struct dsa_switch_tree *dst = ds->dst;
> struct netlink_ext_ack extack = {0};
> - int err, i;
> + int err, port;
>
> if (dst->index == info->tree_index && ds->index == info->sw_index &&
> ds->ops->port_bridge_join)
> @@ -124,13 +124,16 @@ static int dsa_switch_bridge_leave(struct dsa_switch
> *ds,
> * it. That is a good thing, because that lets us handle it and also
> * handle the case where the switch's vlan_filtering setting is global
> * (not per port). When that happens, the correct moment to trigger the
> - * vlan_filtering callback is only when the last port left this bridge.
> + * vlan_filtering callback is only when the last port leaves the last
> + * VLAN-aware bridge.
> */
> if (unset_vlan_filtering && ds->vlan_filtering_is_global) {
> - for (i = 0; i < ds->num_ports; i++) {
> - if (i == info->port)
> - continue;
> - if (dsa_to_port(ds, i)->bridge_dev == info->br) {
> + for (port = 0; port < ds->num_ports; port++) {
> + struct net_device *bridge_dev;
> +
> + bridge_dev = dsa_to_port(ds, port)->bridge_dev;
> +
> + if (bridge_dev && br_vlan_enabled(bridge_dev)) {
> unset_vlan_filtering = false;
> break;
> }
> --
> 2.25.1
Is it the case that all devices in which VLAN filtering is a global
setting are also single-chip? To my _D_SA eyes, it feels like we should
have to iterate over all ports in the tree, not just the switch.
