Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758500AbZJMGEP (ORCPT ); Tue, 13 Oct 2009 02:04:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755970AbZJMGEP (ORCPT ); Tue, 13 Oct 2009 02:04:15 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:54624 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752480AbZJMGEO (ORCPT ); Tue, 13 Oct 2009 02:04:14 -0400 Date: Tue, 13 Oct 2009 08:03:12 +0200 From: Ingo Molnar To: Arjan van de Ven Cc: Siarhei Liakh , linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, James Morris , Andrew Morton , Andi Kleen , Rusty Russell , Thomas Gleixner , "H. Peter Anvin" , David Howells , Aristeu Rozanski Subject: Re: [PATCH V5] x86: NX protection for kernel data Message-ID: <20091013060312.GA3215@elte.hu> References: <817ecb6f0910121803p52a4049ep4a712545d28bba76@mail.gmail.com> <20091012213229.11898c12@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20091012213229.11898c12@infradead.org> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian 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: 1448 Lines: 36 * Arjan van de Ven wrote: > On Mon, 12 Oct 2009 21:03:17 -0400 > Siarhei Liakh wrote: > > > This patch expands functionality of CONFIG_DEBUG_RODATA to set main > > (static) kernel data area as NX. > > The following steps are taken to achieve this: > > 1. Linker script is adjusted so .text always starts and ends on a > > page boundary 2. Linker script is adjusted so .rodata and .data > > always start and end on a page boundary > > 3. void mark_nxdata_nx(void) added to arch/x86/mm/init.c with actual > > functionality: NX is set for all pages from _etext through _end. > > 4. mark_nxdata_nx() called from free_initmem() (after init has been > > released) 5. free_init_pages() sets released memory NX in > > arch/x86/mm/init.c > > > > The patch have been developed for Linux 2.6.31-rc7 x86 by Siarhei > > Liakh and Xuxian Jiang . > > > > I like doing this, but... maybe it is useful to have a diff of the > pagetable dump (PT_DUMP config option) to show the effect, in the > changelog. That'd be like the proof on the pudding... That's a good suggestion. Siarhei Liakh, mind doing that? 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/