Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265482AbUFIBkg (ORCPT ); Tue, 8 Jun 2004 21:40:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265497AbUFIBkg (ORCPT ); Tue, 8 Jun 2004 21:40:36 -0400 Received: from obsidian.spiritone.com ([216.99.193.137]:49383 "EHLO obsidian.spiritone.com") by vger.kernel.org with ESMTP id S265482AbUFIBkZ (ORCPT ); Tue, 8 Jun 2004 21:40:25 -0400 Message-ID: <40C66A7D.6080402@BitWagon.com> Date: Tue, 08 Jun 2004 18:40:13 -0700 From: John Reiser Organization: - User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.2.1) Gecko/20030225 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Ingo Molnar CC: Mike McCormack , Jakub Jelinek , Arjan van de Ven , linux-kernel@vger.kernel.org Subject: Re: WINE + NX (No eXecute) support for x86, 2.6.7-rc2-bk2 References: <40C2B51C.9030203@codeweavers.com> <20040606052615.GA14988@elte.hu> <40C2D5F4.4020803@codeweavers.com> <1086507140.2810.0.camel@laptop.fenrus.com> <20040608092055.GX4736@devserv.devel.redhat.com> <40C59FE9.1010700@codeweavers.com> <20040608103221.GA7632@elte.hu> In-Reply-To: <20040608103221.GA7632@elte.hu> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1200 Lines: 30 Ingo Molnar wrote: > * Mike McCormack wrote: > > >>I did not investigate this, but others who did think that it is not >>possible to create a segment that is reserve only so that does not >>unnecessarily consume virtual memory. Apparently ELF allows it, but >>Linux doesn't. > > > what do you mean by "Linux doesn't"? Current fs/binfmt_elf.c creates at most one ".bss" area, regardless of how many PT_LOAD have .p_filesz < .p_memsz. The .bss area always has PROT_WRITE|PROT_READ page protection, regardless of .p_flags. Thus "Linux doesn't" do as faithful a job as it could with ELF. I submitted "elfdiet" and "bssprot" patches a couple months ago to address these issues. The bssprot patch appeared briefly in -mm for 2.6.[56], but was dropped because of ARCH pain, particularly with the sn2 variant of ia64. The hardware is scarce, and the topic was not sufficiently interesting for those with access to such a box. -- - 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/