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Date: Mon, 11 Nov 2013 21:09:43 +0100
From: Ingo Molnar <mingo@kernel.org>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>, LKML <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        "H. Peter Anvin" <hpa@linux.intel.com>,
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Subject: Re: [tip:x86/kaslr] x86, kaslr: Provide randomness functions
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* H. Peter Anvin <hpa@zytor.com> wrote:

> On 11/11/2013 11:58 AM, Ingo Molnar wrote:
> >>
> >> Use the i8254 if and only if nothing else is available, it isn't safe to
> >> touch on some newer systems.
> > 
> > I concur - the i8254 is probably also a low entry source, given that this 
> > all runs early bootup.
> > 
> 
> Well, it is a 16-bit 1.19318 MHz counter so at least on older systems it 
> is likely to provide at least a modicum on entropy.  On systems with a 
> TSC it is likely to be redundant with the TSC.

Yeah.

Thanks,

	Ingo