[PATCH 3.16 134/254] net/mlx5: Cleanup IRQs in case of unload failure

[Ben Hutchings]

3.16.55-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Moshe Shemesh <moshe@xxxxxxxxxxxx>

commit d6b2785cd55ee72e9608762650b3ef299f801b1b upstream.

When mlx5_stop_eqs fails to destroy any of the eqs it returns with an error.
In such failure flow the function will return without
releasing all EQs irqs and then pci_free_irq_vectors will fail.
Fix by only warn on destroy EQ failure and continue to release other
EQs and their irqs.

It fixes the following kernel trace:
kernel: kernel BUG at drivers/pci/msi.c:352!
...
...
kernel: Call Trace:
kernel: pci_disable_msix+0xd3/0x100
kernel: pci_free_irq_vectors+0xe/0x20
kernel: mlx5_load_one.isra.17+0x9f5/0xec0 [mlx5_core]

Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters")
Signed-off-by: Moshe Shemesh <moshe@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
[bwh: Backported to 3.16: there's no pfault_eq]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
--- a/drivers/net/ethernet/mellanox/mlx5/core/eq.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eq.c
@@ -485,23 +485,28 @@ err1:
 	return err;
 }
 
-int mlx5_stop_eqs(struct mlx5_core_dev *dev)
+void mlx5_stop_eqs(struct mlx5_core_dev *dev)
 {
 	struct mlx5_eq_table *table = &dev->priv.eq_table;
 	int err;
 
 	err = mlx5_destroy_unmap_eq(dev, &table->pages_eq);
 	if (err)
-		return err;
+		mlx5_core_err(dev, "failed to destroy pages eq, err(%d)\n",
+			      err);
 
-	mlx5_destroy_unmap_eq(dev, &table->async_eq);
+	err = mlx5_destroy_unmap_eq(dev, &table->async_eq);
+	if (err)
+		mlx5_core_err(dev, "failed to destroy async eq, err(%d)\n",
+			      err);
 	mlx5_cmd_use_polling(dev);
 
 	err = mlx5_destroy_unmap_eq(dev, &table->cmd_eq);
-	if (err)
+	if (err) {
+		mlx5_core_err(dev, "failed to destroy command eq, err(%d)\n",
+			      err);
 		mlx5_cmd_use_events(dev);
-
-	return err;
+	}
 }
 
 int mlx5_core_eq_query(struct mlx5_core_dev *dev, struct mlx5_eq *eq,
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -759,7 +759,7 @@ int mlx5_create_map_eq(struct mlx5_core_
 		       int nent, u64 mask, const char *name, struct mlx5_uar *uar);
 int mlx5_destroy_unmap_eq(struct mlx5_core_dev *dev, struct mlx5_eq *eq);
 int mlx5_start_eqs(struct mlx5_core_dev *dev);
-int mlx5_stop_eqs(struct mlx5_core_dev *dev);
+void mlx5_stop_eqs(struct mlx5_core_dev *dev);
 int mlx5_core_attach_mcg(struct mlx5_core_dev *dev, union ib_gid *mgid, u32 qpn);
 int mlx5_core_detach_mcg(struct mlx5_core_dev *dev, union ib_gid *mgid, u32 qpn);