From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758380AbYB2TOW (ORCPT ); Fri, 29 Feb 2008 14:14:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751124AbYB2TOO (ORCPT ); Fri, 29 Feb 2008 14:14:14 -0500 Received: from mx1.redhat.com ([66.187.233.31]:36877 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751109AbYB2TON (ORCPT ); Fri, 29 Feb 2008 14:14:13 -0500 Date: Fri, 29 Feb 2008 14:09:52 -0500 From: Jakub Jelinek To: Ollie Wild Cc: Linus Torvalds , Peter Zijlstra , Michael Kerrisk , Andrew Morton , michael.kerrisk@gmail.com, carlos@codesourcery.com, Alan Cox , linux-kernel , drepper@redhat.com, mtk.manpages@gmail.com Subject: Re: [RFC/PATCH] RLIMIT_ARG_MAX Message-ID: <20080229190952.GM24887@devserv.devel.redhat.com> Reply-To: Jakub Jelinek References: <1204119455.6242.403.camel@lappy> <1204305488.6243.113.camel@lappy> <1204306934.6243.119.camel@lappy> <65dd6fd50802291101j3786ee60iec0f3a24f5df9945@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <65dd6fd50802291101j3786ee60iec0f3a24f5df9945@mail.gmail.com> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 29, 2008 at 11:01:38AM -0800, Ollie Wild wrote: > On Fri, Feb 29, 2008 at 10:12 AM, Linus Torvalds > wrote: > > > > So it's not *going* to be exact even with RLIMIT_ARG_MAX, because it's > > going to have all those other issues to contend with - on a 64-bit > > architecture, the argument _pointers_ are often within an order of > > magnitude of the argument strings themselves, and I don't think your patch > > counted them as part of the argument/environemnt size (I was too lazy to > > check the sources, but I'm pretty sure argv/env_start/end is just the > > string space, not the pointers). > > This is precisely why I picked 25% as the maximum argument size ratio. > In practice, that 25% can easily mean 50% or more. If people want to > increase this, it can probably be tweaked somewhat, but switching it > to, say, 50% probably isn't a good idea. I think 50% would be still fine. And, ideally make that MAX (RLIMIT_STACK / 2, 128KB) to avoid regressions for programs which assume they can pass ARG_MAX args+env, even if they have say 192KB stack limit. Jakub