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Subject: Re: [patch] voluntary-preempt-2.6.8.1-P0
From: Lee Revell <rlrevell@joe-job.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Florian Schmidt <mista.tapas@gmx.net>,
       linux-kernel <linux-kernel@vger.kernel.org>,
       Felipe Alfaro Solana <felipe_alfaro@linuxmail.org>
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On Mon, 2004-08-16 at 00:01, Ingo Molnar wrote:
> * Lee Revell <rlrevell@joe-job.com> wrote:
> 
> > I will try next with /dev/random disabled.  Don't most/many new
> > machines have a hardware RNG that would eliminate the need for this
> > code?
> 
> The C3 does have one IIRC, but do Intel CPUs have it too? Also, there's
> the question of trust - how random it truly is. Is it a partly
> pseudo-RNG masked via encryption? /dev/random i know is random, driven
> by random timings of real disks and real network packets. The CPU's HRNG
> is much more encapsulated and can only be blackbox-tested.

According to menuconfig, it looks like Linux supports hardware RNGs from
AMD, Intel, and Via.  Via at least has published a cryptanalysis of
theirs: http://www.via.com.tw/en/viac3/via_c3_padlock_evaluation.pdf.

I am not a crypto expert so I can't comment much more.  Also I have one
of the older C3s without this feature so it's beside the point.

Lee