From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC51DC3A5A4 for ; Sat, 24 Aug 2019 18:19:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9A88E20850 for ; Sat, 24 Aug 2019 18:19:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727827AbfHXSTf (ORCPT ); Sat, 24 Aug 2019 14:19:35 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:47033 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726636AbfHXSTe (ORCPT ); Sat, 24 Aug 2019 14:19:34 -0400 Received: by atrey.karlin.mff.cuni.cz (Postfix, from userid 512) id E32C681339; Sat, 24 Aug 2019 20:19:16 +0200 (CEST) Date: Sat, 24 Aug 2019 20:19:29 +0200 From: Pavel Machek To: linux-kernel@vger.kernel.org Cc: linux-tip-commits@vger.kernel.org, "x86@kernel.org" , Thomas Gleixner , stable@vger.kernel.org, "Rafael J. Wysocki" , Paolo Bonzini , Nathan Chancellor , "linux-pm@vger.kernel.org" , "linux-doc@vger.kernel.org" , Kees Cook , Juergen Gross , Josh Poimboeuf , Jonathan Corbet , Ingo Molnar , "H. Peter Anvin" , Chen Yu , Andrew Morton , Andrew Cooper , Borislav Petkov , Tom Lendacky Subject: Re: [tip: x86/urgent] x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h Message-ID: <20190824181929.GA18551@amd> References: <7543af91666f491547bd86cebb1e17c66824ab9f.1566229943.git.thomas.lendacky@amd.com> <156652264945.9541.4969272027980914591.tip-bot2@tip-bot2> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="UlVJffcvxoiEqYs2" Content-Disposition: inline In-Reply-To: <156652264945.9541.4969272027980914591.tip-bot2@tip-bot2> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --UlVJffcvxoiEqYs2 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri 2019-08-23 01:10:49, tip-bot2 for Tom Lendacky wrote: > The following commit has been merged into the x86/urgent branch of tip: >=20 > Commit-ID: c49a0a80137c7ca7d6ced4c812c9e07a949f6f24 > Gitweb: https://git.kernel.org/tip/c49a0a80137c7ca7d6ced4c812c9e07= a949f6f24 > Author: Tom Lendacky > AuthorDate: Mon, 19 Aug 2019 15:52:35=20 > Committer: Borislav Petkov > CommitterDate: Mon, 19 Aug 2019 19:42:52 +02:00 >=20 > x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h >=20 > There have been reports of RDRAND issues after resuming from suspend on > some AMD family 15h and family 16h systems. This issue stems from a BIOS > not performing the proper steps during resume to ensure RDRAND continues > to function properly. There are quite a few unanswered questions here. a) Is there/should there be CVE for this? b) Can we perform proper steps in kernel, thus making RDRAND usable even when BIOS is buggy? Best regards, Pavel =09 --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --UlVJffcvxoiEqYs2 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAl1hf7EACgkQMOfwapXb+vJr8ACfYYvoVV2o2HMsFRXMI3vauU/K 0fEAn3xhQSvQ1Slrcy2GZlR7YLTFuEsf =//ju -----END PGP SIGNATURE----- --UlVJffcvxoiEqYs2--