Re: [PATCH v3] usb: devio: Add ioctl to disallow detaching kernel USB drivers.

[Greg KH]

On Thu, Feb 04, 2016 at 12:20:57AM -0300, Emilio López wrote:
> From: Reilly Grant <reillyg@xxxxxxxxxxxx>
> 
> The new USBDEVFS_DROP_PRIVILEGES ioctl allows a process to voluntarily
> relinquish the ability to issue other ioctls that may interfere with
> other processes and drivers that have claimed an interface on the
> device.
> 
> Signed-off-by: Reilly Grant <reillyg@xxxxxxxxxxxx>
> Signed-off-by: Emilio López <emilio.lopez@xxxxxxxxxxxxxxx>
> 
> ---
> 
> Changes in v3:
> - Switch ioctl to use a __u32 given the iface qty is capped at 32
> - Reword comments as requested by Alan
> - Allow callers to shrink the allowed interfaces mask

No documentation?  Proof it works?  Test scripts?

This isn't a trivial feature to add, how do we know it is correct?

thanks,

greg k-h