Re: [PATCH] /dev/random: Insufficient of entropy on many architectures

[Geert Uytterhoeven]

On Wed, Sep 11, 2013 at 8:49 AM, Stephan Mueller <smueller@xxxxxxxxxx> wrote:
> __u64 tmp = random_get_fast_cycles() - random_get_fast_cycles();
> if(0 == tmp)
>         return fail;
> return pass;

That will fail if the cycle counter runs at less than say 4 times the
CPU clock...

BTW, I prefer a different name than "random_get_fast_cycles()", as it's better
to have something that returns different and unpredictable numbers than an
actual monotonic cycle counter.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
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