From: Leon Romanovsky <leonro@mellanox.com>
Date: Tue, 13 Aug 2019 13:28:14 +0300
Subject: RDMA/mlx5: Annotate lock dependency in bind/unbind slave port
Patch-mainline: v5.4-rc1
Git-commit: 9dc4cfff115f03e999e5d50a593c83cd0ef4125c
References: jsc#SLE-8446

NULL-ing notifier_call is performed under protection
of mlx5_ib_multiport_mutex lock. Such protection is
not easily spotted and better to be guarded by lockdep
annotation.

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Link: https://lore.kernel.org/r/20190813102814.22350-1-leon@kernel.org
Signed-off-by: Doug Ledford <dledford@redhat.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/hw/mlx5/main.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -5823,7 +5823,6 @@ static void init_delay_drop(struct mlx5_
 		mlx5_ib_warn(dev, "Failed to init delay drop debugfs\n");
 }
 
-/* The mlx5_ib_multiport_mutex should be held when calling this function */
 static void mlx5_ib_unbind_slave_port(struct mlx5_ib_dev *ibdev,
 				      struct mlx5_ib_multiport_info *mpi)
 {
@@ -5833,6 +5832,8 @@ static void mlx5_ib_unbind_slave_port(st
 	int err;
 	int i;
 
+	lockdep_assert_held(&mlx5_ib_multiport_mutex);
+
 	mlx5_ib_cleanup_cong_debugfs(ibdev, port_num);
 
 	spin_lock(&port->mp.mpi_lock);
@@ -5882,13 +5883,14 @@ static void mlx5_ib_unbind_slave_port(st
 	ibdev->port[port_num].roce.last_port_state = IB_PORT_DOWN;
 }
 
-/* The mlx5_ib_multiport_mutex should be held when calling this function */
 static bool mlx5_ib_bind_slave_port(struct mlx5_ib_dev *ibdev,
 				    struct mlx5_ib_multiport_info *mpi)
 {
 	u8 port_num = mlx5_core_native_port_num(mpi->mdev) - 1;
 	int err;
 
+	lockdep_assert_held(&mlx5_ib_multiport_mutex);
+
 	spin_lock(&ibdev->port[port_num].mp.mpi_lock);
 	if (ibdev->port[port_num].mp.mpi) {
 		mlx5_ib_dbg(ibdev, "port %d already affiliated.\n",