Re: [PATCH] net/mlx4: Fix EEH recovery failure

[Gavin Shan <gwshan@linux.vnet.ibm.com>]

On Sat, Nov 22, 2014 at 09:56:47PM +1100, Gavin Shan wrote:

Yishai already had patches fixing the issue. So please ignore
this patch and drop it.

Thanks,
Gavin

>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
>