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Date: Tue, 28 Mar 2017 20:43:08 +0300
From: Krzysztof Kozlowski <krzk@kernel.org>
To: Stephan =?utf-8?Q?M=C3=BCller?= <smueller@chronox.de>
Cc: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>,
        Kukjin Kim <kgene@kernel.org>,
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        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        Arnd Bergmann <arnd@arndb.de>, Olof Johansson <olof@lixom.net>
Subject: Re: [PATCH v3 1/3] crypto: hw_random - Add new Exynos RNG driver
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On Tue, Mar 28, 2017 at 07:41:47PM +0200, Stephan Müller wrote:
> Am Dienstag, 28. März 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