From: Pavel Machek Subject: Re: [PATCH] CPU Jitter RNG: inclusion into kernel crypto API and /dev/random Date: Wed, 13 Nov 2013 18:14:44 +0100 Message-ID: <20131113171444.GA4973@amd.pavel.ucw.cz> References: <2579337.FPgJGgHYdz@tauon> <1391779.T98KINxAMQ@myon.chronox.de> <528367D0.6010900@ladisch.de> <27146362.bQgmetPpTV@tauon> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Clemens Ladisch , Theodore Ts'o , sandy harris , linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, Nicholas Mc Guire To: Stephan Mueller Return-path: Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:47877 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932324Ab3KMROz (ORCPT ); Wed, 13 Nov 2013 12:14:55 -0500 Content-Disposition: inline In-Reply-To: <27146362.bQgmetPpTV@tauon> Sender: linux-crypto-owner@vger.kernel.org List-ID: Hi! > >BTW: MFENCE is not guaranteed to flush the instruction pipeline; you > >need CPUID for that. > > I was not aware of that. Can I simply call the CPUID instruction to read > it or do I have to do something special? Simply call CPUID (warning, it clobbers some registers.). Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html