Re: [PATCH 6/7] vfio: Accpet device file from vfio PCI hot reset path

[Jason Gunthorpe <jgg@nvidia.com>]

On Thu, Mar 16, 2023 at 05:41:55AM -0700, Yi Liu wrote:
> This extends both vfio_file_is_valid() and vfio_file_has_dev() to accept
> device file from the vfio PCI hot reset.
> 
> Signed-off-by: Yi Liu <yi.l.liu@intel.com>
> ---
>  drivers/vfio/vfio_main.c | 23 +++++++++++++++++++----
>  1 file changed, 19 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c
> index fe7446805afd..ebbb6b91a498 100644
> --- a/drivers/vfio/vfio_main.c
> +++ b/drivers/vfio/vfio_main.c
> @@ -1154,13 +1154,23 @@ const struct file_operations vfio_device_fops = {
>  	.mmap		= vfio_device_fops_mmap,
>  };
>  
> +static struct vfio_device *vfio_device_from_file(struct file *file)
> +{
> +	struct vfio_device *device = file->private_data;

Isn't this a df now?

> +	if (file->f_op != &vfio_device_fops)
> +		return NULL;
> +	return device;
> +}

The device has to be bound to be a security proof.

Jason