[Accel-config] Re: [PATCH] accel-config: Replicate driver error codes in idxd.h in library

I just noticed that include/uapi/linux/ndctl.h is distributed as LGPL. I 
wonder if it's possible to change that given only we (Intel) has touched 
this file.

On 7/19/2021 2:13 PM, Thomas, Ramesh wrote:
> Noticed driver idxd.h has GPL license. Library is LGPL and I remember
> LGPL cannot use GPL code. Even if that is changed in newer drivers I am
> not sure if there is any issue with older drivers.
>
> On Mon, Jul 19, 2021 at 01:00:46PM -0700, Dave Jiang wrote:
>> On 7/19/2021 12:35 PM, Thomas, Ramesh wrote:
>>> On Mon, Jul 19, 2021 at 10:50:09AM -0700, Dave Jiang wrote:
>>>> On 7/19/2021 10:34 AM, Thomas, Ramesh wrote:
>>>>> I think copying will have the problem of compiler picking different
>>>>> ones. Library may use the copied version while the app may get the one
>>>>> in /usr/include. Do you think defining new constants would be safer?
>>>> I think instead of pulling the /usr/include version we just depend on
>>>> the copied version exclusively. Then we will have 1 less dependency and
>>>> compile correctly always.
>>> I was also concerned about user apps including the /user/include idxd.h.
>>> Even in libaccel we would need to make assumptions that the constants
>>> used will not diverge from the one driver is using. Since the issue is
>>> only about some constants like the sw cmd_status which is not available
>>> in older idxd.h, I think it is better to define them separately and
>>> privately for the library.
>>>
>> User ABI is considered constant for Linux and if we are changing it,
>> there would be ways to provide backward compatibility. I think making
>> copy of header should be safe. That is why ndctl does that.