From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754234Ab0ARLqN (ORCPT ); Mon, 18 Jan 2010 06:46:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751620Ab0ARLqM (ORCPT ); Mon, 18 Jan 2010 06:46:12 -0500 Received: from casper.infradead.org ([85.118.1.10]:34454 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751471Ab0ARLqM (ORCPT ); Mon, 18 Jan 2010 06:46:12 -0500 Subject: Re: [RFC] [PATCH 1/7] User Space Breakpoint Assistance Layer (UBP) From: Peter Zijlstra To: Avi Kivity Cc: ananth@in.ibm.com, Jim Keniston , Srikar Dronamraju , Ingo Molnar , Arnaldo Carvalho de Melo , utrace-devel , Frederic Weisbecker , Masami Hiramatsu , Maneesh Soni , Mark Wielaard , LKML In-Reply-To: <4B543F93.3060509@redhat.com> References: <20100111122521.22050.3654.sendpatchset@srikar.in.ibm.com> <20100111122529.22050.32596.sendpatchset@srikar.in.ibm.com> <1263467289.4244.288.camel@laptop> <1263498366.4875.25.camel@localhost.localdomain> <1263546228.4244.343.camel@laptop> <20100115093831.GC26396@in.ibm.com> <1263549014.4244.374.camel@laptop> <4B53213C.9050303@redhat.com> <1263739939.557.20938.camel@twins> <4B5325CF.5000001@redhat.com> <1263740593.557.20967.camel@twins> <4B53661A.9090907@redhat.com> <1263800752.4283.19.camel@laptop> <4B543F93.3060509@redhat.com> Content-Type: text/plain; charset="UTF-8" Date: Mon, 18 Jan 2010 12:45:40 +0100 Message-ID: <1263815140.4283.309.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2010-01-18 at 13:01 +0200, Avi Kivity wrote: > If we reserve some address space, you don't add any heisenbugs (at > least, not any additional ones over emulation). Even if we don't, > address space layout randomization means we're not keeping the address > space layout constant between runs anyway. Well, it still limits the number of probes to the reserved area. If you want more you need to grow the area.. which then changes the state.