Re: [PATCH 1/2] powerpc: drop dependency on <asm/machdep.h> in archrandom.h

From: Yury Norov
Date: Mon Jul 25 2022 - 19:35:18 EST


On Mon, Jul 25, 2022 at 11:39:39PM +0200, Andy Shevchenko wrote:
> On Mon, Jul 25, 2022 at 6:19 PM Yury Norov <yury.norov@xxxxxxxxx> wrote:
> > On Mon, Jul 25, 2022 at 09:28:12AM +0200, Andy Shevchenko wrote:
> > > On Sun, Jul 24, 2022 at 12:19 AM Yury Norov <yury.norov@xxxxxxxxx> wrote:
>
> ...
>
> > > > EXPORT_SYMBOL_GPL(pm_power_off);
> > >
> > > ^^^ (Note this and read below)
> > >
> > > ...
> > >
> > > > +EXPORT_SYMBOL(arch_get_random_seed_long);
> > >
> > > It can't be like this. Brief browsing of the callees shows that.
> >
> > Is my understanding correct that you're suggesting to make it GPL?
> >
> > ppc_md is exported with EXPORT_SYMBOL(), and the function is in header,
> > so it's available for non-GPL code now. I don't want to change it.
>
> The symbols your function calls are GPL. As far as I understand (not a
> lawyer!) it logically one may not call GPL and pretend to be non-GPL.

Can you explain what you mean in details?

The function is:
static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
{
if (ppc_md.get_random_seed)
return ppc_md.get_random_seed(v);

return false;
}

ppc_md is non-GPL:
77 /* The main machine-dep calls structure
78 */
79 struct machdep_calls ppc_md;
80 EXPORT_SYMBOL(ppc_md);

And get_random_seed is initialized in in arch/powerpc/platforms/powernv/rng.c
with different functions that are static and not exported at all.

I don't understand where arch_get_random_seed_long calls GPL...