Re: [PATCH v3 1/3] crypto: hw_random - Add new Exynos RNG driver

From: Krzysztof Kozlowski
Date: Tue Mar 28 2017 - 13:44:02 EST


On Tue, Mar 28, 2017 at 07:41:47PM +0200, Stephan MÃller wrote:
> Am Dienstag, 28. MÃrz 2017, 18:48:24 CEST schrieb Krzysztof Kozlowski:
>
> Hi Krzysztof,
>
> > I tested a little bit and:
> > 1. Seeding with some value
> > 2. generating random,
> > 3. kcapi_rng_destroy+kcrng_init, (I cannot do a hardware reset except
> > reboot of entire system)
> > 4. seeding with the same value as in (1) - different random numbers.
> >
> > Doing a system reboot and repeating above - different random numbers
> > (all are different: step (2) and in (4)).
> >
> > Your test case also produces different random values every time.
>
> Then I would assume that simply adding an outer loop to your for() loop to
> inject seed larger than the minimum required seed size should be fine.

Yes, makes sense. I'll send an updated version of patch.

Best regards,
Krzysztof