kernel: backport switchdev fix for bridge in bridge configurations

This patch fixes the forwarding behavior of bridge in bridge
configurations with DSA.

Without it, the configuration of the upper bridge might overwrite
settings of the lower bridge. For example, a vlan-aware bridge
with DSA interfaces in it might be offloaded to the DSA hardware. If the
bridge interface itself gets slave of a different bridge without vlan
filtering, the vlan filtering setting of the lower bridge is overwritten
by the upper bridge, which results in an incorrect hardware
configuration.

This was backported from kernel 5.7.

Ref: https://lore.kernel.org/netdev/20191222192235.GK25745@shell.armlinux.org.uk/
Fixes: FS#3996
Signed-off-by: Fabian Bläse <fabian@blaese.de>
(cherry picked from commit c50ece58c4)
This commit is contained in:
Fabian Bläse 2021-08-29 21:21:35 +02:00 committed by Hauke Mehrtens
parent a300e3c890
commit c37a9e506c

View File

@ -0,0 +1,60 @@
From 07c6f9805f12f1bb538ef165a092b300350384aa Mon Sep 17 00:00:00 2001
From: Russell King <rmk+kernel@armlinux.org.uk>
Date: Wed, 26 Feb 2020 17:14:21 +0000
Subject: [PATCH] net: switchdev: do not propagate bridge updates across
bridges
When configuring a tree of independent bridges, propagating changes
from the upper bridge across a bridge master to the lower bridge
ports brings surprises.
For example, a lower bridge may have vlan filtering enabled. It
may have a vlan interface attached to the bridge master, which may
then be incorporated into another bridge. As soon as the lower
bridge vlan interface is attached to the upper bridge, the lower
bridge has vlan filtering disabled.
This occurs because switchdev recursively applies its changes to
all lower devices no matter what.
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Tested-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/switchdev/switchdev.c | 9 +++++++++
1 file changed, 9 insertions(+)
--- a/net/switchdev/switchdev.c
+++ b/net/switchdev/switchdev.c
@@ -476,6 +476,9 @@ static int __switchdev_handle_port_obj_a
* necessary to go through this helper.
*/
netdev_for_each_lower_dev(dev, lower_dev, iter) {
+ if (netif_is_bridge_master(lower_dev))
+ continue;
+
err = __switchdev_handle_port_obj_add(lower_dev, port_obj_info,
check_cb, add_cb);
if (err && err != -EOPNOTSUPP)
@@ -528,6 +531,9 @@ static int __switchdev_handle_port_obj_d
* necessary to go through this helper.
*/
netdev_for_each_lower_dev(dev, lower_dev, iter) {
+ if (netif_is_bridge_master(lower_dev))
+ continue;
+
err = __switchdev_handle_port_obj_del(lower_dev, port_obj_info,
check_cb, del_cb);
if (err && err != -EOPNOTSUPP)
@@ -579,6 +585,9 @@ static int __switchdev_handle_port_attr_
* necessary to go through this helper.
*/
netdev_for_each_lower_dev(dev, lower_dev, iter) {
+ if (netif_is_bridge_master(lower_dev))
+ continue;
+
err = __switchdev_handle_port_attr_set(lower_dev, port_attr_info,
check_cb, set_cb);
if (err && err != -EOPNOTSUPP)