From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752224AbaEAW2h (ORCPT ); Thu, 1 May 2014 18:28:37 -0400 Received: from imap.thunk.org ([74.207.234.97]:44680 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751762AbaEAW2f (ORCPT ); Thu, 1 May 2014 18:28:35 -0400 Date: Thu, 1 May 2014 22:28:32 +0000 From: tytso@mit.edu To: Andy Lutomirski Cc: "H. Peter Anvin" , "linux-kernel@vger.kernel.org" , kvm list , Florian Weimer , Kees Cook Subject: Re: random: Providing a seed value to VM guests Message-ID: <20140501222832.GD25829@thunk.org> Mail-Followup-To: tytso@mit.edu, Andy Lutomirski , "H. Peter Anvin" , "linux-kernel@vger.kernel.org" , kvm list , Florian Weimer , Kees Cook References: <20140501192618.GA25829@thunk.org> <900441a0-24e8-4976-ad35-3971805b9f34@email.android.com> <20140501203910.GB25829@thunk.org> <5362B618.50602@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: tytso@thunk.org X-SA-Exim-Scanned: No (on imap.thunk.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 01, 2014 at 02:06:13PM -0700, Andy Lutomirski wrote: > > I still don't see the point. What does this do better than virtio-rng? I believe you had been complaining about how complicated it was to set up virtio? And this complexity is also an issue if we want to use it to initialize the RNG used for the kernel text ASLR --- which has to be done very early in the boot process, and where making something as simple as possible is a Good Thing. And since we would want to use RDRAND/RDSEED if it is available *anyway*, perhaps in combination with other things, why not use the RDRAND/RDSEED interface? - Ted