From 3f55a410b2327dd0a709e08729ffd963a5b78dd7 Mon Sep 17 00:00:00 2001
From: Dima Chumak <dchumak@nvidia.com>
Date: Wed, 30 Jun 2021 14:56:32 +0300
Subject: [PATCH] net/mlx5: Lag, fix multipath lag activation
Git-commit: 2f8b6161cca5fb34b0065e2eac8bb2b61b7bfe87
Patch-mainline: v5.15-rc1
References: stable-5.14.4
[ Upstream commit 2f8b6161cca5fb34b0065e2eac8bb2b61b7bfe87 ]
When handling FIB_EVENT_ENTRY_REPLACE event for a new multipath route,
lag activation can be missed if a stale (struct lag_mp)->mfi pointer
exists, which was associated with an older multipath route that had been
removed.
Normally, when a route is removed, it triggers mlx5_lag_fib_event(),
which handles FIB_EVENT_ENTRY_DEL and clears mfi pointer. But, if
mlx5_lag_check_prereq() condition isn't met, for example when eswitch is
in legacy mode, the fib event is skipped and mfi pointer becomes stale.
Fix by resetting mfi pointer to NULL in mlx5_deactivate_lag().
Fixes: 8a66e4585979 ("net/mlx5: Change ownership model for lag")
Signed-off-by: Dima Chumak <dchumak@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/ethernet/mellanox/mlx5/core/lag.c | 1 +
drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c | 8 ++++++++
drivers/net/ethernet/mellanox/mlx5/core/lag_mp.h | 2 ++
3 files changed, 11 insertions(+)
--- a/drivers/net/ethernet/mellanox/mlx5/core/lag.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lag.c
@@ -305,6 +305,7 @@ static int mlx5_deactivate_lag(struct ml
int err;
ldev->flags &= ~MLX5_LAG_MODE_FLAGS;
+ mlx5_lag_mp_reset(ldev);
if (ldev->shared_fdb) {
mlx5_eswitch_offloads_destroy_single_fdb(ldev->pf[MLX5_LAG_P1].dev->priv.eswitch,
--- a/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
@@ -302,6 +302,14 @@ static int mlx5_lag_fib_event(struct not
return NOTIFY_DONE;
}
+void mlx5_lag_mp_reset(struct mlx5_lag *ldev)
+{
+ /* Clear mfi, as it might become stale when a route delete event
+ * has been missed, see mlx5_lag_fib_route_event().
+ */
+ ldev->lag_mp.mfi = NULL;
+}
+
int mlx5_lag_mp_init(struct mlx5_lag *ldev)
{
struct lag_mp *mp = &ldev->lag_mp;
--- a/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.h
@@ -21,11 +21,13 @@ struct lag_mp {
#ifdef CONFIG_MLX5_ESWITCH
+void mlx5_lag_mp_reset(struct mlx5_lag *ldev);
int mlx5_lag_mp_init(struct mlx5_lag *ldev);
void mlx5_lag_mp_cleanup(struct mlx5_lag *ldev);
#else /* CONFIG_MLX5_ESWITCH */
+static inline void mlx5_lag_mp_reset(struct mlx5_lag *ldev) {};
static inline int mlx5_lag_mp_init(struct mlx5_lag *ldev) { return 0; }
static inline void mlx5_lag_mp_cleanup(struct mlx5_lag *ldev) {}