From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753989Ab0JNAor (ORCPT ); Wed, 13 Oct 2010 20:44:47 -0400 Received: from terminus.zytor.com ([198.137.202.10]:48032 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751784Ab0JNAoq (ORCPT ); Wed, 13 Oct 2010 20:44:46 -0400 Message-ID: <4CB65262.3070507@zytor.com> Date: Wed, 13 Oct 2010 17:44:18 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.9) Gecko/20100921 Fedora/3.1.4-1.fc13 Thunderbird/3.1.4 MIME-Version: 1.0 To: David Rientjes CC: Ingo Molnar , Thomas Gleixner , Casey Dahlin , x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [patch] x86: allow ZONE_DMA to be configurable References: <4CB64D8F.9080800@zytor.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/13/2010 05:42 PM, David Rientjes wrote: > You can already set the lowmem_reserve_ratio via > /proc/sys/vm/lowmem_reserve_ratio. And why is it then so hard to put in a single line in /etc/sysctl.conf for you? > We've run without ZONE_DMA for a couple years because we don't have such > hardware limitations and would appreciate the ability to disable it with a > config option rather than hacking the kernel to get it to compile. I'm > sure Casey would as well as you can see in the thread "A question about > ZONE_DMA". > > I don't see the harm in being able to conveniently disable the zone if you > know what you're doing. There are going to be a lot of very strange bug reports as a result. -hpa