[PATCH] net/mlx4: Fix EEH recovery failure

Gavin Shan
2014-11-22T10:57:05Z

The patch fixes couple of EEH recovery failures on PPC PowerNV
platform:

* Release reserved memory regions in mlx4_pci_err_detected().
Otherwise, __mlx4_init_one() fails because of reserving
same memory regions recursively.
* Disable PCI device in mlx4_pci_err_detected(). Otherwise,
pci_enable_device() in __mlx4_init_one() doesn't enable
the PCI device because it's already in enabled state indicated
by struct pci_dev::enable_cnt.
* Don't clear struct mlx4_priv instance in mlx4_pci_err_detected().
Otherwise, __mlx4_init_one() runs into kernel crash because
of dereferencing to NULL pointer.

With the patch applied, EEH recovery for mlx4 adapter succeeds on PPC
PowerNV platform.

# lspci
0003:0f:00.0 Network controller: Mellanox Technologies \
MT27500 Family [ConnectX-3]

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
---
drivers/net/ethernet/mellanox/mlx4/main.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index 90de6e1..e118ac9 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -2809,7 +2809,6 @@ static void mlx4_unload_one(struct pci_dev *pdev)
kfree(dev->caps.qp1_proxy);
kfree(dev->dev_vfs);

- memset(priv, 0, sizeof(*priv));
priv->pci_dev_data = pci_dev_data;
priv->removed = 1;
}
@@ -2900,6 +2899,8 @@ static pci_ers_result_t mlx4_pci_err_detected(struct pci_dev *pdev,
pci_channel_state_t state)
{
mlx4_unload_one(pdev);
+ pci_release_regions(pdev);
+ pci_disable_device(pdev);

return state == pci_channel_io_perm_failure ?
PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_NEED_RESET;
--
1.8.3.2