Re: [PATCH v3 2/5] random,x86: Add arch_get_slow_rng_u64

[Daniel Borkmann]

On 07/17/2014 12:59 AM, H. Peter Anvin wrote:
> On 07/16/2014 03:40 PM, Andy Lutomirski wrote:
> > On Wed, Jul 16, 2014 at 3:13 PM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote:
> > > My personal preference is to defer this until some user shows up.  I
> > > think that even this would be too complicated for KASLR, which is the
> > > only extremely early-boot user that I found.
> > >
> > > Hmm.  Does the prandom stuff want to use this?
> >
> > prandom isn't even using rdrand.  I'd suggest fixing this separately,
> > or even just waiting until someone goes and deletes prandom.
>
> prandom is exactly the opposite; it is designed for when we need
> possibly low quality random numbers very quickly.  RDRAND is actually
> too slow.

Yep, prandom() is quite heavily used in the network stack where it's
traded for speed.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/