From: Vladimir Oltean <vladimir.oltean@xxxxxxx> [ Upstream commit c1930148a3941f891ddbd76fceaa4e10a957ccf2 ] Currently we are unable to ping a bridge on top of a felix switch which uses the ocelot-8021q tagger. The packets are dropped on the ingress of the user port and the 'drop_local' counter increments (the counter which denotes drops due to no valid destinations). Dumping the PGID tables, it becomes clear that the PGID_SRC of the user port is zero, so it has no valid destinations. But looking at the code, the cpu_fwd_mask (the bit mask of DSA tag_8021q ports) is clearly missing from the forwarding mask of ports that are under a bridge. So this has always been broken. Looking at the version history of the patch, in v7 https://patchwork.kernel.org/project/netdevbpf/patch/20210125220333.1004365-12-olteanv@xxxxxxxxx/ the code looked like this: /* Standalone ports forward only to DSA tag_8021q CPU ports */ unsigned long mask = cpu_fwd_mask; (...) } else if (ocelot->bridge_fwd_mask & BIT(port)) { mask |= ocelot->bridge_fwd_mask & ~BIT(port); while in v8 (the merged version) https://patchwork.kernel.org/project/netdevbpf/patch/20210129010009.3959398-12-olteanv@xxxxxxxxx/ it looked like this: unsigned long mask; (...) } else if (ocelot->bridge_fwd_mask & BIT(port)) { mask = ocelot->bridge_fwd_mask & ~BIT(port); So the breakage was introduced between v7 and v8 of the patch. Fixes: e21268efbe26 ("net: dsa: felix: perform switch setup for tag_8021q") Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx> Link: https://lore.kernel.org/r/20210817160425.3702809-1-vladimir.oltean@xxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/ethernet/mscc/ocelot.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c index adfb9781799e..2948d731a1c1 100644 --- a/drivers/net/ethernet/mscc/ocelot.c +++ b/drivers/net/ethernet/mscc/ocelot.c @@ -1334,6 +1334,7 @@ void ocelot_apply_bridge_fwd_mask(struct ocelot *ocelot) struct net_device *bond = ocelot_port->bond; mask = ocelot_get_bridge_fwd_mask(ocelot, bridge); + mask |= cpu_fwd_mask; mask &= ~BIT(port); if (bond) { mask &= ~ocelot_get_bond_mask(ocelot, bond, -- 2.30.2
