From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933934AbXCPA3T (ORCPT ); Thu, 15 Mar 2007 20:29:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992450AbXCPA3H (ORCPT ); Thu, 15 Mar 2007 20:29:07 -0400 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:57191 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S933934AbXCPA2x (ORCPT ); Thu, 15 Mar 2007 20:28:53 -0400 Date: Fri, 16 Mar 2007 01:31:44 +0000 From: Alan Cox To: Hugh Dickins Cc: Andrew Morton , Dan Aloni , linux-kernel@vger.kernel.org Subject: Re: thread stacks and strict vm overcommit accounting Message-ID: <20070316013144.0d81c72d@lxorguk.ukuu.org.uk> In-Reply-To: References: <20070313163320.GA28104@localdomain> <20070315110621.9a9defaf.akpm@linux-foundation.org> <20070315233343.662b019c@lxorguk.ukuu.org.uk> <20070315153613.3d2eaf10.akpm@linux-foundation.org> X-Mailer: Claws Mail 2.8.1 (GTK+ 2.10.8; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > > > With a typical size as a fuzz factor preaccounted in later kernels. > > > > Where's that done? > > I don't know what Alan is referring to there. fs/exec.c - we add 20 pages to the stack vma size initially. > We've no more committed to providing each instance with 8MB of stack, > than we've committed to providing each instance with RLIMIT_AS of > address space. The rlimits are limits, not commitments, surely? Yes, its just that the C programming language is utterly and mindbogglingly broken when it comes to resource exhaustion for the stack. Alan