Re: [PATCH 1/4] VFIO: Probe new devices in a live VFIO group with the VFIO driver

[Alex Williamson <alex.williamson@redhat.com>]

On Thu,  9 Jun 2016 15:09:29 +0300
Ilya Lesokhin <ilyal@mellanox.com> wrote:

> When a new device is added to a live VFIO group,
> use driver_override to force the device to be probed by
> the VFIO driver.
> 
> Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
> ---
>  drivers/vfio/vfio.c | 18 ++++++++++++++----
>  1 file changed, 14 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 6fd6fa5..32bc1b4 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -646,6 +646,7 @@ static int vfio_dev_viable(struct device *dev, void *data)
>  static int vfio_group_nb_add_dev(struct vfio_group *group, struct device *dev)
>  {
>  	struct vfio_device *device;
> +	struct pci_dev *pdev;
>  
>  	/* Do we already know about it?  We shouldn't */
>  	device = vfio_group_get_device(group, dev);
> @@ -658,10 +659,19 @@ static int vfio_group_nb_add_dev(struct vfio_group *group, struct device *dev)
>  	if (!atomic_read(&group->container_users))
>  		return 0;
>  
> -	/* TODO Prevent device auto probing */
> -	WARN(1, "Device %s added to live group %d!\n", dev_name(dev),
> -	     iommu_group_id(group->iommu_group));
> -
> +	if (dev_is_pci(dev)) {

declare pdev here.

> +		/* a device that shares a group with another VFIO
> +		 * device should also be probed by VFIO
> +		 */

Use existing comment style:

/*
 * comment
 */

> +		pdev = to_pci_dev(dev);
> +		if (pdev->driver_override)
> +			kfree(pdev->driver_override);
> +		pdev->driver_override = kstrdup("vfio-pci", GFP_KERNEL);

kstrdup can fail.  Probably want to issue a dev_info message about
capturing the device as well.  Thanks,

Alex

> +	} else {
> +		/* TODO Prevent device auto probing */
> +		WARN(1, "Device %s added to live group %d!\n", dev_name(dev),
> +		     iommu_group_id(group->iommu_group));
> +	}
>  	return 0;
>  }
>