[PATCH v12 1/2] IB/mlx5: Fix transport-domain rollback and initialize lb mutex earlier

[Prathamesh Deshpande]

mlx5_ib_alloc_transport_domain() allocates a transport domain and then
may fail in mlx5_ib_enable_lb(). In that case, the allocated TD is leaked.

Fix this by deallocating the TD when mlx5_ib_enable_lb() returns an
error. Also return 0 explicitly in the no-loopback-capability success
branch, and move dev->lb.mutex initialization to mlx5_ib_stage_init_init().

Destroy dev->lb.mutex in the matching cleanup path and in init failure
paths after the mutex is initialized.

Fixes: 146d2f1af324 ("IB/mlx5: Allocate a Transport Domain for each ucontext")
Signed-off-by: Prathamesh Deshpande <prathameshdeshpande7@xxxxxxxxx>
---
 drivers/infiniband/hw/mlx5/main.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index e02bfb1479f5..f6d9841c2bcf 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -2068,9 +2068,13 @@ static int mlx5_ib_alloc_transport_domain(struct mlx5_ib_dev *dev, u32 *tdn,
 	if ((MLX5_CAP_GEN(dev->mdev, port_type) != MLX5_CAP_PORT_TYPE_ETH) ||
 	    (!MLX5_CAP_GEN(dev->mdev, disable_local_lb_uc) &&
 	     !MLX5_CAP_GEN(dev->mdev, disable_local_lb_mc)))
-		return err;
+		return 0;
+
+	err = mlx5_ib_enable_lb(dev, true, false);
+	if (err)
+		mlx5_cmd_dealloc_transport_domain(dev->mdev, *tdn, uid);
 
-	return mlx5_ib_enable_lb(dev, true, false);
+	return err;
 }
 
 static void mlx5_ib_dealloc_transport_domain(struct mlx5_ib_dev *dev, u32 tdn,
@@ -4464,6 +4468,7 @@ static void mlx5_ib_stage_init_cleanup(struct mlx5_ib_dev *dev)
 	mlx5_ib_cleanup_multiport_master(dev);
 	WARN_ON(!xa_empty(&dev->odp_mkeys));
 	mutex_destroy(&dev->cap_mask_mutex);
+	mutex_destroy(&dev->lb.mutex);
 	WARN_ON(!xa_empty(&dev->sig_mrs));
 	WARN_ON(!bitmap_empty(dev->dm.memic_alloc_pages, MLX5_MAX_MEMIC_PAGES));
 	mlx5r_macsec_dealloc_gids(dev);
@@ -4486,17 +4491,19 @@ static int mlx5_ib_stage_init_init(struct mlx5_ib_dev *dev)
 		dev->port[i].roce.last_port_state = IB_PORT_DOWN;
 	}
 
+	mutex_init(&dev->lb.mutex);
+
 	err = mlx5r_cmd_query_special_mkeys(dev);
 	if (err)
-		return err;
+		goto err_lb_mutex;
 
 	err = mlx5r_macsec_init_gids_and_devlist(dev);
 	if (err)
-		return err;
+		goto err_lb_mutex;
 
 	err = mlx5_ib_init_multiport_master(dev);
 	if (err)
-		goto err;
+		goto err_gids;
 
 	err = set_has_smi_cap(dev);
 	if (err)
@@ -4536,8 +4543,10 @@ static int mlx5_ib_stage_init_init(struct mlx5_ib_dev *dev)
 	mlx5_ib_data_direct_cleanup(dev);
 err_mp:
 	mlx5_ib_cleanup_multiport_master(dev);
-err:
+err_gids:
 	mlx5r_macsec_dealloc_gids(dev);
+err_lb_mutex:
+	mutex_destroy(&dev->lb.mutex);
 	return err;
 }
 
@@ -4786,11 +4795,6 @@ static int mlx5_ib_stage_caps_init(struct mlx5_ib_dev *dev)
 	if (err)
 		return err;
 
-	if ((MLX5_CAP_GEN(dev->mdev, port_type) == MLX5_CAP_PORT_TYPE_ETH) &&
-	    (MLX5_CAP_GEN(dev->mdev, disable_local_lb_uc) ||
-	     MLX5_CAP_GEN(dev->mdev, disable_local_lb_mc)))
-		mutex_init(&dev->lb.mutex);
-
 	if (MLX5_CAP_GEN_64(dev->mdev, general_obj_types) &
 			MLX5_GENERAL_OBJ_TYPES_CAP_VIRTIO_NET_Q) {
 		err = mlx5_ib_init_var_region(dev);
-- 
2.43.0