Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757867Ab0DGMZe (ORCPT ); Wed, 7 Apr 2010 08:25:34 -0400 Received: from khc.piap.pl ([195.187.100.11]:46384 "EHLO khc.piap.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757713Ab0DGMZb (ORCPT ); Wed, 7 Apr 2010 08:25:31 -0400 X-Greylist: delayed 541 seconds by postgrey-1.27 at vger.kernel.org; Wed, 07 Apr 2010 08:25:30 EDT From: Krzysztof Halasa To: Frank Hu Cc: "H. Peter Anvin" , Joel Fernandes , hayfeng Lee , linux-kernel@vger.kernel.org, linux-kernel@zh-kernel.org, kernelnewbies@nl.linux.org Subject: Re: why choose 896MB to the start point of ZONE_HIGHMEM References: <4BBB7AC9.5060008@zytor.com> <4BBB8F07.60401@zytor.com> Date: Wed, 07 Apr 2010 14:16:27 +0200 In-Reply-To: (Frank Hu's message of "Tue, 6 Apr 2010 13:15:49 -0700") Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 674 Lines: 16 Frank Hu writes: > thought that you can only configure how to split the VM like 1G/3G or > 2G/2G. But the DMA zone size, the 128MB space for I/O is not > configurable. The NORMAL zone size will be deducted based on the VM > Split and some hard coded DMA zone and 128 MB space size. Only the DMA zone size if fixed - a hardware property of PC/AT-style DMA controllers and ISA bus. -- Krzysztof Halasa -- 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/