Re: [PATCH] hpsa: refine the pci enble/disable handling

[Tomas Henzl <thenzl@redhat.com>]

Steve, Joe,
any chance you could review this patch and verify the sw reset case?
Thanks, Tomas

On 06/12/2014 05:29 PM, Tomas Henzl wrote:
> When a second(kdump) kernel starts and the hard reset method is used
> the driver calls pci_disable_device without previously enabling it,
> so the kernel shows a warning -
> [   16.876248] WARNING: at drivers/pci/pci.c:1431 pci_disable_device+0x84/0x90()
> [   16.882686] Device hpsa
> disabling already-disabled device
> ...
> This patch fixes it, in addition to this I tried to balance also some other pairs
> of enable/disable device in the driver.
> Unfortunately I wasn't able to verify the functionality for the case of a sw reset,
> because of a lack of proper hw.
>
> Signed-off-by: Tomas Henzl <thenzl@redhat.com>
> ---
> diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
> index 5858600..67c41b9 100644
> --- a/drivers/scsi/hpsa.c
> +++ b/drivers/scsi/hpsa.c
> @@ -5983,7 +5983,6 @@ static int hpsa_kdump_hard_reset_controller(struct pci_dev *pdev)
>  	/* Turn the board off.  This is so that later pci_restore_state()
>  	 * won't turn the board on before the rest of config space is ready.
>  	 */
> -	pci_disable_device(pdev);
>  	pci_save_state(pdev);
>  
>  	/* find the first memory BAR, so we can find the cfg table */
> @@ -6031,11 +6030,6 @@ static int hpsa_kdump_hard_reset_controller(struct pci_dev *pdev)
>  		goto unmap_cfgtable;
>  
>  	pci_restore_state(pdev);
> -	rc = pci_enable_device(pdev);
> -	if (rc) {
> -		dev_warn(&pdev->dev, "failed to enable device.\n");
> -		goto unmap_cfgtable;
> -	}
>  	pci_write_config_word(pdev, 4, command_register);
>  
>  	/* Some devices (notably the HP Smart Array 5i Controller)
> @@ -6548,6 +6542,12 @@ static int hpsa_init_reset_devices(struct pci_dev *pdev)
>  	if (!reset_devices)
>  		return 0;
>  
> +	rc = pci_enable_device(pdev);
> +	if (rc) {
> +		dev_warn(&pdev->dev, "failed to enable device.\n");
> +		return -ENODEV;
> +	}
> +
>  	/* Reset the controller with a PCI power-cycle or via doorbell */
>  	rc = hpsa_kdump_hard_reset_controller(pdev);
>  
> @@ -6556,10 +6556,11 @@ static int hpsa_init_reset_devices(struct pci_dev *pdev)
>  	 * "performant mode".  Or, it might be 640x, which can't reset
>  	 * due to concerns about shared bbwc between 6402/6404 pair.
>  	 */
> -	if (rc == -ENOTSUPP)
> -		return rc; /* just try to do the kdump anyhow. */
> -	if (rc)
> -		return -ENODEV;
> +	if (rc) {
> +		if (rc != -ENOTSUPP) /* just try to do the kdump anyhow. */
> +			rc = -ENODEV;
> +		goto out_disable; 
> +	}
>  
>  	/* Now try to get the controller to respond to a no-op */
>  	dev_warn(&pdev->dev, "Waiting for controller to respond to no-op\n");
> @@ -6570,7 +6571,11 @@ static int hpsa_init_reset_devices(struct pci_dev *pdev)
>  			dev_warn(&pdev->dev, "no-op failed%s\n",
>  					(i < 11 ? "; re-trying" : ""));
>  	}
> -	return 0;
> +
> +out_disable:
> +
> +	pci_disable_device(pdev);
> +	return rc;
>  }
>  
>  static int hpsa_allocate_cmd_pool(struct ctlr_info *h)
> @@ -6722,6 +6727,7 @@ static void hpsa_undo_allocations_after_kdump_soft_reset(struct ctlr_info *h)
>  		iounmap(h->transtable);
>  	if (h->cfgtable)
>  		iounmap(h->cfgtable);
> +	pci_disable_device(h->pdev);
>  	pci_release_regions(h->pdev);
>  	kfree(h);
>  }