Re: [PATCH net 1/1] iavf: Fix shutdown pci callback to match the remove one

[Leon Romanovsky <leon@kernel.org>]

On Fri, Jan 13, 2023 at 01:50:12PM -0800, Tony Nguyen wrote:
> From: Slawomir Laba <slawomirx.laba@intel.com>
> 
> Make the flow for pci shutdown be the same to the pci remove.
> 
> iavf_shutdown was implementing an incomplete version
> of iavf_remove. It misses several calls to the kernel like
> iavf_free_misc_irq, iavf_reset_interrupt_capability, iounmap
> that might break the system on reboot or hibernation.
> 
> Implement the call of iavf_remove directly in iavf_shutdown to
> close this gap.
> 
> Fixes: 5eae00c57f5e ("i40evf: main driver core")
> Signed-off-by: Slawomir Laba <slawomirx.laba@intel.com>
> Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
> Tested-by: Marek Szlosek <marek.szlosek@intel.com>
> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
> ---
>  drivers/net/ethernet/intel/iavf/iavf_main.c | 40 +++++++--------------
>  1 file changed, 12 insertions(+), 28 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
> index adc02adef83a..34c9bd62546b 100644
> --- a/drivers/net/ethernet/intel/iavf/iavf_main.c
> +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
> @@ -4812,34 +4812,6 @@ int iavf_process_config(struct iavf_adapter *adapter)
>  	return 0;
>  }
>  
> -/**
> - * iavf_shutdown - Shutdown the device in preparation for a reboot
> - * @pdev: pci device structure
> - **/
> -static void iavf_shutdown(struct pci_dev *pdev)
> -{
> -	struct iavf_adapter *adapter = iavf_pdev_to_adapter(pdev);
> -	struct net_device *netdev = adapter->netdev;
> -
> -	netif_device_detach(netdev);
> -
> -	if (netif_running(netdev))
> -		iavf_close(netdev);
> -
> -	if (iavf_lock_timeout(&adapter->crit_lock, 5000))
> -		dev_warn(&adapter->pdev->dev, "%s: failed to acquire crit_lock\n", __func__);
> -	/* Prevent the watchdog from running. */
> -	iavf_change_state(adapter, __IAVF_REMOVE);
> -	adapter->aq_required = 0;
> -	mutex_unlock(&adapter->crit_lock);
> -
> -#ifdef CONFIG_PM
> -	pci_save_state(pdev);
> -
> -#endif
> -	pci_disable_device(pdev);
> -}
> -
>  /**
>   * iavf_probe - Device Initialization Routine
>   * @pdev: PCI device information struct
> @@ -5177,6 +5149,18 @@ static void iavf_remove(struct pci_dev *pdev)
>  	pci_disable_device(pdev);
>  }
>  
> +/**
> + * iavf_shutdown - Shutdown the device in preparation for a reboot
> + * @pdev: pci device structure
> + **/
> +static void iavf_shutdown(struct pci_dev *pdev)
> +{
> +	iavf_remove(pdev);
> +
> +	if (system_state == SYSTEM_POWER_OFF)
> +		pci_set_power_state(pdev, PCI_D3hot);

Why do you need it? and why does "system_state == SYSTEM_POWER_OFF" line
exist in small number of old drivers?

What is missing in PCI core power state management, which pushes you
to set D3 state in hibernation?

Thanks


> +}
> +
>  static SIMPLE_DEV_PM_OPS(iavf_pm_ops, iavf_suspend, iavf_resume);
>  
>  static struct pci_driver iavf_driver = {
> -- 
> 2.38.1
>