Re: [PATCH 1/2] powerpc: export ppc_tb_freq so that modules can reference it

[Josh Boyer <jwboyer@gmail.com>]

On Sat, Sep 18, 2010 at 11:34 AM, Kumar Gala <kumar.gala@freescale.com> wro=
te:
>
> On Sep 18, 2010, at 9:36 AM, Tabi Timur-B04825 wrote:
>
>> On Sep 17, 2010, at 10:14 PM, "Benjamin Herrenschmidt" <benh@kernel.cras=
hing.org> wrote:
>>
>>> On Fri, 2010-09-17 at 20:20 -0500, Timur Tabi wrote:
>>>> I don't see any reason to limit it to GPL drivers. =A0Not only that, b=
ut
>>>> then we'll have this:
>>>
>>> I do
>>
>> Can you elaborate on that, or are you just going to pull rank on me?
>>
>>>
>>>> EXPORT_SYMBOL(ppc_proc_freq);
>>>> EXPORT_SYMBOL_GPL(ppc_tb_freq);
>>>>
>>>> That just looks dumb.
>>>
>>> Right, so send a patch to fix the first one too :-)
>
> I don't think either of these should be EXPORT_SYMBOL_GPL. =A0Why shouldn=
't a binary module be allowed to know these frequencies? =A0My view is why =
preclude anyone from using this how they want. =A0If they want to live in t=
he gray area so be it. =A0Who am I to say they shouldn't have that choice.
>

It is not, in my opinion, about what is technically possible and what
isn't.  The kernel is licensed under the GPL.  This is a Linux kernel
only symbol.  One would be hard pressed to claim they have a driver
that wasn't written for Linux that happens to need that symbol.  As a
member of the Linux kernel community, I find it important to encourage
the contribution of code back to the kernel, and this is one way to
help that.  This isn't BSD.

Besides, a developer is free to export it however they wish in their
own kernel tree.  They can deviate from mainline if they so choose.

josh