Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265883AbUFXWze (ORCPT ); Thu, 24 Jun 2004 18:55:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265792AbUFXWzd (ORCPT ); Thu, 24 Jun 2004 18:55:33 -0400 Received: from holomorphy.com ([207.189.100.168]:27533 "EHLO holomorphy.com") by vger.kernel.org with ESMTP id S265886AbUFXWvl (ORCPT ); Thu, 24 Jun 2004 18:51:41 -0400 Date: Thu, 24 Jun 2004 15:51:21 -0700 From: William Lee Irwin III To: Andrea Arcangeli Cc: Andrew Morton , nickpiggin@yahoo.com.au, tiwai@suse.de, ak@suse.de, ak@muc.de, tripperda@nvidia.com, discuss@x86-64.org, linux-kernel@vger.kernel.org Subject: Re: [discuss] Re: 32-bit dma allocations on 64-bit platforms Message-ID: <20040624225121.GS21066@holomorphy.com> Mail-Followup-To: William Lee Irwin III , Andrea Arcangeli , Andrew Morton , nickpiggin@yahoo.com.au, tiwai@suse.de, ak@suse.de, ak@muc.de, tripperda@nvidia.com, discuss@x86-64.org, linux-kernel@vger.kernel.org References: <20040624164258.1a1beea3.ak@suse.de> <20040624152946.GK30687@dualathlon.random> <40DAF7DF.9020501@yahoo.com.au> <20040624165200.GM30687@dualathlon.random> <20040624165629.GG21066@holomorphy.com> <20040624145441.181425c8.akpm@osdl.org> <20040624220823.GO21066@holomorphy.com> <20040624224529.GA30687@dualathlon.random> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040624224529.GA30687@dualathlon.random> User-Agent: Mutt/1.5.5.1+cvs20040105i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 948 Lines: 20 On Fri, Jun 25, 2004 at 12:45:29AM +0200, Andrea Arcangeli wrote: > Luckily this problem doesn't fall in this scenario and it's trivial to > reproduce if you've >= 2G of ram. I still have here the testcase google > sent me years ago when this problem seen the light during 2.4.1x. They > used mlock, but it's even simpler to reproduce it with a single malloc + > bzero (note: no mlock). The few mbytes of lowmem left won't last long if > you load some big app after that. Well, there are magic numbers here we need to explain to get a testcase runnable on more machines than just x86 boxen with exactly 2GB RAM. Where do the 2GB and 1GB come from? Is it that 1GB is the size of the upper zone? -- wli - 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/