Re: [PATCH v4 2/3] random: introduce generic vDSO getrandom() implementation

Jason A. Donenfeld
2022-11-19T12:12:19Z

On Sat, Nov 19, 2022 at 12:43:31PM +0100, Jason A. Donenfeld wrote:
> On Sat, Nov 19, 2022 at 07:51:21AM +0000, Christophe Leroy wrote:
> >
> >
> > Le 19/11/2022 à 01:04, Jason A. Donenfeld a écrit :
> > > On Sat, Nov 19, 2022 at 12:55:02AM +0100, Jason A. Donenfeld wrote:
> > >> Sorry if I'm a bit slow here to grok what's up.
> >
> > Maybe I should also have mentionned commit ce7d8056e38b ("powerpc/vdso:
> > Prepare for switching VDSO to generic C implementation.") for you to
> > have a complete picture.
> >
> > >
> > > Okay, I think I see it now. That's a complicated patch for a simple idea
> > > because gettime is more complicated than getrandom. I suspect what you
> > > want is something like the below, correct? Seems easy enough.
> >
> > Yes it is exactly that, powerpc will then call __cvdso_getrandom_data()
> > directly and pass rng_info pointer.
>
> Okay, I'll do that and send out a v+1.

Alright, new series posted here, with those changes. Let me know if that
is workable for you. Since a lot of the vDSO is tied up (currently) with
timekeeping stuff, it's a bit tricky adding things to it like this. I've
done the best I can to keep it clean and such, but if you want to play
around with wiring up powerpc, that might prove to be an interesting
exercise in shaking out inconsistencies. New series is here:
https://lore.kernel.org/lkml/20221119120929.2963813-1-Jason@zx2c4.com/T

Jason