From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH v3 2/5] random,x86: Add arch_get_slow_rng_u64
Date: Wed, 16 Jul 2014 15:59:57 -0700
Message-ID: <53C703ED.2010605@zytor.com>
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Cc: kvm list <kvm@vger.kernel.org>, "Theodore Ts'o" <tytso@mit.edu>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Kees Cook <keescook@chromium.org>, X86 ML <x86@kernel.org>,
	Daniel Borkmann <dborkman@redhat.com>,
	Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>,
	Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>,
	Gleb Natapov <gleb@kernel.org>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Bandan Das <bsd@redhat.com>
To: Andy Lutomirski <luto@amacapital.net>
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On 07/16/2014 03:40 PM, Andy Lutomirski wrote:
> On Wed, Jul 16, 2014 at 3:13 PM, Andy Lutomirski <luto@amacapital.net> wrote:
>> My personal preference is to defer this until some user shows up.  I
>> think that even this would be too complicated for KASLR, which is the
>> only extremely early-boot user that I found.
>>
>> Hmm.  Does the prandom stuff want to use this?
> 
> prandom isn't even using rdrand.  I'd suggest fixing this separately,
> or even just waiting until someone goes and deletes prandom.
> 

prandom is exactly the opposite; it is designed for when we need
possibly low quality random numbers very quickly.  RDRAND is actually
too slow.

	-hpa