6.12-stable review patch. If anyone has any objections, please let me know.
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From: Jonas Gorski jonas.gorski@gmail.com
[ Upstream commit 692eb9f8a5b71d852e873375d20cf5da7a046ea6 ]
When Linux sends out untagged traffic from a port, it will enter the CPU port without any VLAN tag, even if the port is a member of a vlan filtering bridge with a PVID egress untagged VLAN.
This makes the CPU port's PVID take effect, and the PVID's VLAN table entry controls if the packet will be tagged on egress.
Since commit 45e9d59d3950 ("net: dsa: b53: do not allow to configure VLAN 0") we remove bridged ports from VLAN 0 when joining or leaving a VLAN aware bridge. But we also clear the untagged bit, causing untagged traffic from the controller to become tagged with VID 0 (and priority 0).
Fix this by not touching the untagged map of VLAN 0. Additionally, always keep the CPU port as a member, as the untag map is only effective as long as there is at least one member, and we would remove it when bridging all ports and leaving no standalone ports.
Since Linux (and the switch) treats VLAN 0 tagged traffic like untagged, the actual impact of this is rather low, but this also prevented earlier detection of the issue.
Fixes: 45e9d59d3950 ("net: dsa: b53: do not allow to configure VLAN 0") Signed-off-by: Jonas Gorski jonas.gorski@gmail.com Reviewed-by: Florian Fainelli florian.fainelli@broadcom.com Reviewed-by: Vladimir Oltean olteanv@gmail.com Link: https://patch.msgid.link/20250602194914.1011890-1-jonas.gorski@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/dsa/b53/b53_common.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/net/dsa/b53/b53_common.c b/drivers/net/dsa/b53/b53_common.c index 79039c0941c20..71c30a81c36db 100644 --- a/drivers/net/dsa/b53/b53_common.c +++ b/drivers/net/dsa/b53/b53_common.c @@ -2036,9 +2036,6 @@ int b53_br_join(struct dsa_switch *ds, int port, struct dsa_bridge bridge,
b53_get_vlan_entry(dev, pvid, vl); vl->members &= ~BIT(port); - if (vl->members == BIT(cpu_port)) - vl->members &= ~BIT(cpu_port); - vl->untag = vl->members; b53_set_vlan_entry(dev, pvid, vl); }
@@ -2117,8 +2114,7 @@ void b53_br_leave(struct dsa_switch *ds, int port, struct dsa_bridge bridge) }
b53_get_vlan_entry(dev, pvid, vl); - vl->members |= BIT(port) | BIT(cpu_port); - vl->untag |= BIT(port) | BIT(cpu_port); + vl->members |= BIT(port); b53_set_vlan_entry(dev, pvid, vl); } }