[PATCH 6.19 436/781] net: renesas: rswitch: fix forwarding offload statemachine

Greg Kroah-Hartman
2026-02-25T01:36:02Z

From: Michael Dege <michael.dege@renesas.com>

[ Upstream commit e9a5073a98d940837cbb95e71eed1f28f48e7b30 ]

A change of the port state of one port, caused the state of another
port to change. This behvior was unintended.

Fixes: b7502b1043de ("net: renesas: rswitch: add offloading for L2 switching")
Signed-off-by: Michael Dege <michael.dege@renesas.com>
Link: https://patch.msgid.link/20260206-fix-offloading-statemachine-v3-1-07bfba07d03e@renesas.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/renesas/rswitch_l2.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/renesas/rswitch_l2.c b/drivers/net/ethernet/renesas/rswitch_l2.c
index 4a69ec77d69c6..9433cd8adced9 100644
--- a/drivers/net/ethernet/renesas/rswitch_l2.c
+++ b/drivers/net/ethernet/renesas/rswitch_l2.c
@@ -1,7 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
/* Renesas Ethernet Switch device driver
*
- * Copyright (C) 2025 Renesas Electronics Corporation
+ * Copyright (C) 2025 - 2026 Renesas Electronics Corporation
*/

#include <linux/err.h>
@@ -60,6 +60,7 @@ static void rswitch_update_l2_hw_learning(struct rswitch_private *priv)
static void rswitch_update_l2_hw_forwarding(struct rswitch_private *priv)
{
struct rswitch_device *rdev;
+ bool new_forwarding_offload;
unsigned int fwd_mask;

/* calculate fwd_mask with zeroes in bits corresponding to ports that
@@ -73,8 +74,9 @@ static void rswitch_update_l2_hw_forwarding(struct rswitch_private *priv)
}

rswitch_for_all_ports(priv, rdev) {
- if ((rdev_for_l2_offload(rdev) && rdev->forwarding_requested) ||
- rdev->forwarding_offloaded) {
+ new_forwarding_offload = (rdev_for_l2_offload(rdev) && rdev->forwarding_requested);
+
+ if (new_forwarding_offload || rdev->forwarding_offloaded) {
/* Update allowed offload destinations even for ports
* with L2 offload enabled earlier.
*
@@ -84,13 +86,10 @@ static void rswitch_update_l2_hw_forwarding(struct rswitch_private *priv)
priv->addr + FWPC2(rdev->port));
}

- if (rdev_for_l2_offload(rdev) &&
- rdev->forwarding_requested &&
- !rdev->forwarding_offloaded) {
+ if (new_forwarding_offload && !rdev->forwarding_offloaded)
rswitch_change_l2_hw_offloading(rdev, true, false);
- } else if (rdev->forwarding_offloaded) {
+ else if (!new_forwarding_offload && rdev->forwarding_offloaded)
rswitch_change_l2_hw_offloading(rdev, false, false);
- }
}
}

--
2.51.0