Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756552Ab1E2T5W (ORCPT ); Sun, 29 May 2011 15:57:22 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:50901 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756500Ab1E2T5U (ORCPT ); Sun, 29 May 2011 15:57:20 -0400 Date: Sun, 29 May 2011 21:56:57 +0200 From: Ingo Molnar To: "H. Peter Anvin" Cc: Linus Torvalds , Dan Rosenberg , "Rafael J. Wysocki" , Tony Luck , linux-kernel@vger.kernel.org, davej@redhat.com, kees.cook@canonical.com, davem@davemloft.net, eranian@google.com, adobriyan@gmail.com, penberg@kernel.org, Arjan van de Ven , Andrew Morton , Valdis.Kletnieks@vt.edu, pageexec@freemail.hu Subject: Re: [RFC][PATCH] Randomize kernel base address on boot Message-ID: <20110529195657.GF13539@elte.hu> References: <20110527174644.GG4356@elte.hu> <4DDFE52D.4070308@zytor.com> <20110528121820.GB12059@elte.hu> <4DE19DC3.7090106@zytor.com> <20110529124702.GE26627@elte.hu> <4DE28E1E.60207@zytor.com> <20110529184409.GA9835@elte.hu> <4DE295FE.1020506@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4DE295FE.1020506@zytor.com> User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 772 Lines: 24 * H. Peter Anvin wrote: > On 05/29/2011 11:44 AM, Ingo Molnar wrote: > > > > We could put a 2MB hole between end of text (end of X) and start of > > readonly data (start of NX), and another 2MB hole between end of > > readonly and start of data. > > > > It still means you have memory which is X-mapped when it doesn't need to > be, since there will be RAM in that region. But it ought to be rather harmless in this particular case, because the high alias addresses are all randomized! Thanks, Ingo -- 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/