On Mon, Mar 22, 2021 at 06:52:58PM +0100, Tobias Waldekranz wrote:
> 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.
Correct, I might revisit this if I ever get my hands on a board with
sja1105 switches in a real multi-switch tree, and not in disjoint trees
as I have had access to so far.
