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Date: Sun, 26 Mar 2017 21:09:59 +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>,
        Javier Martinez Canillas <javier@osg.samsung.com>,
        Matt Mackall <mpm@selenic.com>,
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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
Message-ID: <20170326180959.rmps6pj5376l45fz@kozik-lap>
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On Sun, Mar 26, 2017 at 07:05:48PM +0200, Stephan Müller wrote:
> Am Sonntag, 26. März 2017, 18:46:02 CEST schrieb PrasannaKumar Muralidharan:
> 
> Hi 	Krzysztof,
> 
> > >> > +       if (slen < EXYNOS_RNG_SEED_SIZE) {
> > >> > +               dev_warn(rng->dev, "Seed too short (only %u bytes)\n",
> > >> > slen); +               return -EINVAL;
> > >> > +       }
> > >> 
> > >> Will it be helpful to print the required seed size?
> > > 
> > > It is in /proc/crypto... It is not a problem to print it but isn't that
> > > redundant?
> > 
> > Not necessary if it is already available.
> 
> Maybe the dev_warn should be removed. Note, unprivileged user space can 
> trigger this warning by simply invoking the seeding operation over and over 
> again with an insufficient seed size. This would clutter the log.

Makes sense. The generic dev_dbg() before would bring enough
information.

Best regards,
Krzysztof