Re: [PATCH v11 03/11] firmware: xilinx: Add zynqmp IOCTL API for device control

Michal Simek
2018-09-10T12:35:30Z

On 9.9.2018 21:20, Moritz Fischer wrote:
> Hi Olof,
>
> On Sat, Sep 8, 2018 at 6:18 PM, Olof Johansson <olof@lixom.net> wrote:
>> Hi,
>>
>> On Fri, Aug 3, 2018 at 10:53 AM, Jolly Shah <jolly.shah@xilinx.com> wrote:
>>> From: Rajan Vaja <rajanv@xilinx.com>
>>>
>>> Add ZynqMP firmware IOCTL API to control and configure
>>> devices like PLLs, SD, Gem, etc.
>>>
>>> Signed-off-by: Rajan Vaja <rajanv@xilinx.com>
>>> Signed-off-by: Jolly Shah <jollys@xilinx.com>
>>
>> This patch worries me somewhat. It's a transparent pass-through ioctl
>> driver. Is there a spec available for what the implemented IOCTLs are?
>>
>> Should some of them be proper drivers instead of an opaque
>> pass-through like this? Could some of them have stability impact on
>> the platform such that there are security concerns and the list of
>> arguments should somehow be sanitized?
>
> I tend to agree with this, good catch.
>
>> What's the intended usecase anyway? Just a debug tool during
>> development, or something that you expect heavy use of by some
>> userspace middleware?
>
> I suspect it is another attempt to make userspace clocks/plls work? Scary.

none is trying to do that as far as I know.

Thanks,
Michal