[PATCH net V2 2/3] net/mlx5: SD, Keep multi-pf debugfs entries on primary

[Tariq Toukan <tariqt@nvidia.com>]

From: Shay Drory <shayd@nvidia.com>

mlx5_sd_init() creates the "multi-pf" debugfs directory under the
primary device debugfs root, but stored the dentry in the calling
device's sd struct. When sd_cleanup() run on a different PF,
this leads to using the wrong sd->dfs for removing entries, which
results in memory leak and an error in when re-creating the SD.[1]

Fix it by explicitly storing the debugfs dentry in the primary
device sd struct and use it for all per-group files.

[1]
debugfs: 'multi-pf' already exists in '0000:08:00.1'

Fixes: 4375130bf527 ("net/mlx5: SD, Add debugfs")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
 .../net/ethernet/mellanox/mlx5/core/lib/sd.c  | 20 ++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/sd.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/sd.c
index a34860ad231a..a5e2e0a411df 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/sd.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/sd.c
@@ -465,9 +465,13 @@ int mlx5_sd_init(struct mlx5_core_dev *dev)
 	if (err)
 		goto err_sd_unregister;
 
-	sd->dfs = debugfs_create_dir("multi-pf", mlx5_debugfs_get_dev_root(primary));
-	debugfs_create_x32("group_id", 0400, sd->dfs, &sd->group_id);
-	debugfs_create_file("primary", 0400, sd->dfs, primary, &dev_fops);
+	primary_sd->dfs =
+		debugfs_create_dir("multi-pf",
+				   mlx5_debugfs_get_dev_root(primary));
+	debugfs_create_x32("group_id", 0400, primary_sd->dfs,
+			   &primary_sd->group_id);
+	debugfs_create_file("primary", 0400, primary_sd->dfs, primary,
+			    &dev_fops);
 
 	mlx5_sd_for_each_secondary(i, primary, pos) {
 		char name[32];
@@ -477,7 +481,8 @@ int mlx5_sd_init(struct mlx5_core_dev *dev)
 			goto err_unset_secondaries;
 
 		snprintf(name, sizeof(name), "secondary_%d", i - 1);
-		debugfs_create_file(name, 0400, sd->dfs, pos, &dev_fops);
+		debugfs_create_file(name, 0400, primary_sd->dfs, pos,
+				    &dev_fops);
 
 	}
 
@@ -495,7 +500,8 @@ int mlx5_sd_init(struct mlx5_core_dev *dev)
 	mlx5_sd_for_each_secondary_to(i, primary, to, pos)
 		sd_cmd_unset_secondary(pos);
 	sd_cmd_unset_primary(primary);
-	debugfs_remove_recursive(sd->dfs);
+	debugfs_remove_recursive(primary_sd->dfs);
+	primary_sd->dfs = NULL;
 err_sd_unregister:
 	mlx5_devcom_comp_unlock(sd->devcom);
 	sd_unregister(dev);
@@ -520,14 +526,14 @@ void mlx5_sd_cleanup(struct mlx5_core_dev *dev)
 
 	primary = mlx5_sd_get_primary(dev);
 	primary_sd = mlx5_get_sd(primary);
-
 	if (primary_sd->state != MLX5_SD_STATE_UP)
 		goto out_unlock;
 
 	mlx5_sd_for_each_secondary(i, primary, pos)
 		sd_cmd_unset_secondary(pos);
 	sd_cmd_unset_primary(primary);
-	debugfs_remove_recursive(sd->dfs);
+	debugfs_remove_recursive(primary_sd->dfs);
+	primary_sd->dfs = NULL;
 
 	sd_info(primary, "group id %#x, uncombined\n", sd->group_id);
 	primary_sd->state = MLX5_SD_STATE_DESTROYING;
-- 
2.44.0