From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262714AbVA0TyA (ORCPT ); Thu, 27 Jan 2005 14:54:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262717AbVA0TyA (ORCPT ); Thu, 27 Jan 2005 14:54:00 -0500 Received: from mx2.elte.hu ([157.181.151.9]:23748 "EHLO mx2.elte.hu") by vger.kernel.org with ESMTP id S262714AbVA0Txp (ORCPT ); Thu, 27 Jan 2005 14:53:45 -0500 Date: Thu, 27 Jan 2005 20:53:32 +0100 From: Ingo Molnar To: Dave Jones , Pavel Machek , Arjan van de Ven , linux-kernel@vger.kernel.org, akpm@osdl.org, torvalds@osdl.org Subject: Re: Patch 1/6 introduce sysctl Message-ID: <20050127195332.GA12532@elte.hu> References: <20050127101117.GA9760@infradead.org> <20050127101201.GB9760@infradead.org> <20050127181525.GA4784@elf.ucw.cz> <20050127191120.GA10460@elte.hu> <20050127194603.GA31127@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050127194603.GA31127@redhat.com> User-Agent: Mutt/1.4.1i X-ELTE-SpamVersion: MailScanner 4.31.6-itk1 (ELTE 1.2) SpamAssassin 2.63 ClamAV 0.73 X-ELTE-VirusStatus: clean X-ELTE-SpamCheck: no X-ELTE-SpamCheck-Details: score=-4.9, required 5.9, autolearn=not spam, BAYES_00 -4.90 X-ELTE-SpamLevel: X-ELTE-SpamScore: -4 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Dave Jones wrote: > On Thu, Jan 27, 2005 at 08:11:20PM +0100, Ingo Molnar wrote: > > > so, i'm glad to report, it's a non-issue. Sometimes developers want to > > disable randomisation during development (quick'n'easy hacks get quicker > > and easier - e.g. if you watch an address within gdb), so having the > > capability for unprivileged users to disable randomisation on the fly is > > useful and Fedora certainly offers that, but from a support and > > bug-reporting POV it's not a problem. > > It's worth noting that some users have found the randomisation disable > useful for running things like xine/mplayer etc with win32 codecs that > seem to just segfault otherwise. These things seem to be incredibly > fragile to address space layout changes, which is a good argument for > trying to avoid these wierdo formats where possible in favour of free > codecs. yes, this was by far the biggest problem randomisation caused. Note that while Fedora offers a personality-hack to disable randomisation on the fly, which Wine could have made use of to have the fix automatically; Alexandre didnt want to rely on it in Wine because that flag's semantics (PER_LINUX32) were not upstream. (and i very much agree with Alexandre on that call). But once something like this is upstream i believe Wine can (and will) have a robust legacy-binary-format loader that is not affected by randomisation effects, with minimal changes. Ingo