From: Suresh Devarakonda <ramad@nvidia.com>
Date: Wed, 26 Oct 2022 14:51:49 +0100
Subject: net/mlx5: Fix crash during sync firmware reset
Patch-mainline: v6.1-rc3
Git-commit: aefb62a9988749703435e941704624949a80a2a9
References: jsc#PED-1549

When setting Bluefield to DPU NIC mode using mlxconfig tool +  sync
firmware reset flow, we run into scenario where the host was not
eswitch manager at the time of mlx5 driver load but becomes eswitch manager
after the sync firmware reset flow. This results in null pointer
access of mpfs structure during mac filter add. This change prevents null
pointer access but mpfs table entries will not be added.

Fixes: 5ec697446f46 ("net/mlx5: Add support for devlink reload action fw activate")
Signed-off-by: Suresh Devarakonda <ramad@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Bodong Wang <bodong@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Link: https://lore.kernel.org/r/20221026135153.154807-12-saeed@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlx5/core/lib/mpfs.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/mpfs.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/mpfs.c
@@ -122,7 +122,7 @@ void mlx5_mpfs_cleanup(struct mlx5_core_
 {
 	struct mlx5_mpfs *mpfs = dev->priv.mpfs;
 
-	if (!MLX5_ESWITCH_MANAGER(dev))
+	if (!mpfs)
 		return;
 
 	WARN_ON(!hlist_empty(mpfs->hash));
@@ -137,7 +137,7 @@ int mlx5_mpfs_add_mac(struct mlx5_core_d
 	int err = 0;
 	u32 index;
 
-	if (!MLX5_ESWITCH_MANAGER(dev))
+	if (!mpfs)
 		return 0;
 
 	mutex_lock(&mpfs->lock);
@@ -185,7 +185,7 @@ int mlx5_mpfs_del_mac(struct mlx5_core_d
 	int err = 0;
 	u32 index;
 
-	if (!MLX5_ESWITCH_MANAGER(dev))
+	if (!mpfs)
 		return 0;
 
 	mutex_lock(&mpfs->lock);