Re: [PATCH 0/1] refcount: restore kref_get and kref_put to non-GPL status

[John Hubbard]

On 03/08/2017 02:12 AM, Greg Kroah-Hartman wrote:
> On Wed, Mar 08, 2017 at 01:59:33AM -0800, John Hubbard wrote:
> > On 03/08/2017 01:48 AM, Greg Kroah-Hartman wrote:
> > > On Wed, Mar 08, 2017 at 01:25:48AM -0800, john.hubbard@xxxxxxxxx wrote:
> > > > From: John Hubbard <jhubbard@xxxxxxxxxx>
> > > >
> > > > Hi,
> > > >
> > > > Say, I'm 99% sure that this was just an oversight, so
> > > > I'm sticking my neck out here and floating a patch to
> > > > Put Things Back. I'm hoping that there is not some
> > > > firm reason to GPL-protect the basic kref_get and
> > > > kref_put routines, because when designing some
> > > > recent new (open-source, yay!) device drivers, we relied
> > > > on this being available, even for MIT-licensed code.
> > >
> > > MIT-licensed code should be just fine with GPL symbols, just use the
> > > correct MODULE_LICENSE() setting and all is good.
> >
> > Actually, we're still using this license string:
> >
> >    MODULE_LICENSE("MIT");
> >
> > which I understand does *not* grant access to GPL symbols. So I guess we'd
> > have to switch over to "MIT/GPL", if I understand correctly, in order to be
> > all correct here.
>
> You need to write this as:
> 	MODULE_LICENSE("Dual MIT/GPL");
> for the linker to handle this properly as that is the string it is
> looking for.

Yes, understood. I thought from your previous response that maybe "MIT" alone was 
*intended* to provide access, but this makes sense and matches what I'd thought 
earlier. And of course, your other point (about the header itself being licensed) 
overrides this, but it's nice to get clarification on this detail, as long as I'm 
stuck--for now--on "MIT".

Appreciate your time and quick responses on this, I know it's probably tiresome to 
answer these sorts of questions.

thanks again,
john h


> thanks,
>
> greg k-h