net/mlx4_core: Fix potential kernel Oops in res tracker during Dom0 driver unload

Currently the slave and master resources are deleted after master freed
all bitmaps. If any resources were not properly cleaned up during the
shutdown process, an Oops would result.

Fix so that delete slave (only) resources during cleanup. Master resources
are cleaned up during unload process, and need not separately be cleaned.

Note that during cleanup, we need to split the resource-tracker freeing
functionality.

Before removing all the bitmaps, we free any leftover slave resources.
However, we can only remove the resource tracker linked list after
all bitmap frees, since some of the freeing functions (e.g.,
mlx4_cleanup_eq_table) use paravirtualized FW commands which expect
the resource tracker linked list to be present.

Found-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 1 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index 8eed1f269323..2e94f76f8016 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -2069,6 +2069,10 @@ static void mlx4_remove_one(struct pci_dev *pdev)
                         mlx4_CLOSE_PORT(dev, p);
                 }
 
+                if (mlx4_is_master(dev))
+                        mlx4_free_resource_tracker(dev,
+                                                   RES_TR_FREE_SLAVES_ONLY);
+
                 mlx4_cleanup_counters_table(dev);
                 mlx4_cleanup_mcg_table(dev);
                 mlx4_cleanup_qp_table(dev);
@@ -2081,7 +2085,8 @@ static void mlx4_remove_one(struct pci_dev *pdev)
                 mlx4_cleanup_pd_table(dev);
 
                 if (mlx4_is_master(dev))
-                        mlx4_free_resource_tracker(dev);
+                        mlx4_free_resource_tracker(dev,
+                                                   RES_TR_FREE_STRUCTS_ONLY);
 
                 iounmap(priv->kar);
                 mlx4_uar_free(dev, &priv->driver_uar);