Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756744Ab2BWXEp (ORCPT ); Thu, 23 Feb 2012 18:04:45 -0500 Received: from 1wt.eu ([62.212.114.60]:62592 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755884Ab2BWXEo (ORCPT ); Thu, 23 Feb 2012 18:04:44 -0500 Date: Fri, 24 Feb 2012 00:04:30 +0100 From: Willy Tarreau To: "H. Peter Anvin" Cc: Linus Torvalds , Greg Kroah-Hartman , stable@vger.kernel.org, Raphael Prevost , Suresh Siddha , Linux Kernel Mailing List Subject: Re: [PATCH 0/5] i387: stable kernel backport Message-ID: <20120223230430.GE1306@1wt.eu> References: <20120223204832.GA30322@kroah.com> <4F46A6EC.8050804@zytor.com> <20120223211016.GA16275@kroah.com> <20120223215242.GA1306@1wt.eu> <20120223222733.GB1306@1wt.eu> <4F46C253.106@zytor.com> <20120223225227.GD1306@1wt.eu> <4F46C3CF.40303@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4F46C3CF.40303@zytor.com> User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1702 Lines: 41 On Thu, Feb 23, 2012 at 02:55:11PM -0800, H. Peter Anvin wrote: > On 02/23/2012 02:52 PM, Willy Tarreau wrote: > > On Thu, Feb 23, 2012 at 02:48:51PM -0800, H. Peter Anvin wrote: > >> On 02/23/2012 02:38 PM, Linus Torvalds wrote: > >>> > >>> You'd still need an x86-32 machine to test on, because x86-64 was > >>> immune to this issue. > >>> > >>> But yeah, the impact of this seems to be small enough that for older > >>> kernels (which are likely used on older systems for maintenance > >>> anyway) disabling AES-NI on x86-32 really might be the way to go. > >>> > >> > >> That would really suck for users of encrypted hard disks. > > > > Peter, do you really think there are that many ? I think I only saw > > AES-NI on recent 64-bit capable chips, and it's been a while that > > users have been installing 64-bit distros on such machines. Note that > > I'm not advocating for breaking existing setups, just that I'm surprized > > by this combination (aes-ni + 32-bit). > > > > There are still people running 32-bit systems because they have some odd > compatibility constraints but now have to deal with corporate or other > security constraints; they may also have been using disk encryption > since before AES-NI was in but doing it on the integer side is way slower. Indeed the combination looks plausible :-) > This is not AES-NI in the interrupt path, but I don't think there is a > knob for that. OK. So let's hope this works then ! Willy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/