From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932138AbWAJN3r (ORCPT ); Tue, 10 Jan 2006 08:29:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932213AbWAJN3r (ORCPT ); Tue, 10 Jan 2006 08:29:47 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:44223 "EHLO mx3.mail.elte.hu") by vger.kernel.org with ESMTP id S932138AbWAJN3q (ORCPT ); Tue, 10 Jan 2006 08:29:46 -0500 Date: Tue, 10 Jan 2006 14:29:57 +0100 From: Ingo Molnar To: Jens Axboe Cc: linux-kernel@vger.kernel.org, Andrew Morton , Linus Torvalds Subject: Re: 2G memory split Message-ID: <20060110132957.GA28666@elte.hu> References: <20060110125852.GA3389@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060110125852.GA3389@suse.de> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: 0.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=0.0 required=5.9 tests=AWL autolearn=no SpamAssassin version=3.0.3 0.0 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Jens Axboe wrote: > Hi, > > It does annoy me that any 1G i386 machine will end up with 1/8th of > the memory as highmem. A patch like this one has been used in various > places since the early 2.4 days at least, is there a reason why it > isn't merged yet? Note I just hacked this one up, but similar patches > abound I'm sure. Bugs are mine. yes, i made it totally configurable in 2.4 days: 1:3, 2/2 and 3:1 splits were possible. It was a larger patch to enable all this across x86, but the Kconfig portion was removed a bit later because people _frequently_ misconfigured their kernels and then complained about the results. so for now the trivial solution is to change the "C" to "8" in the following line in include/asm-i386/page.h: > #define __PAGE_OFFSET (0xC0000000) instead of editing your .config :-) Maybe we could try the Kconfig solution again, but it'll need alot better documentation, dependency on KERNEL_DEBUG and some heavy warnings all around. Ingo