Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752661Ab2JFASA (ORCPT ); Fri, 5 Oct 2012 20:18:00 -0400 Received: from terminus.zytor.com ([198.137.202.10]:42956 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751016Ab2JFAR6 (ORCPT ); Fri, 5 Oct 2012 20:17:58 -0400 Message-ID: <506F78A2.3050408@zytor.com> Date: Fri, 05 Oct 2012 17:17:38 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120911 Thunderbird/15.0.1 MIME-Version: 1.0 To: "Eric W. Biederman" CC: Yinghai Lu , Konrad Rzeszutek Wilk , Jacob Shin , Stefano Stabellini , Thomas Gleixner , Ingo Molnar , Tejun Heo , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 04/13] x86, mm: Revert back good_end setting for 64bit References: <1348991844-12285-1-git-send-email-yinghai@kernel.org> <1348991844-12285-5-git-send-email-yinghai@kernel.org> <20121003165105.GA30214@jshin-Toonie> <20121004164630.GB2244@phenom.dumpdata.com> <871uhcsk93.fsf@xmission.com> <87ehlcr4et.fsf@xmission.com> In-Reply-To: <87ehlcr4et.fsf@xmission.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1289 Lines: 38 On 10/05/2012 02:32 PM, Eric W. Biederman wrote: > Yinghai Lu writes: > >> On Fri, Oct 5, 2012 at 2:04 PM, Eric W. Biederman wrote: >>>>> Is there a git commit that explains what the 'big range' problem is? >>> >>> At least on x86_64 this was recently tested and anywhere below 4G is >>> good, and there is a patch floating around somewhere to remove this >>> issue. >> >> patch for kernel or kexec-tools? > > kernel. > > The sgi guys needed a kdump kernel with 1G of ram to dump their all of > the memory on one of their crazy large machines and so investigated > this. > > Basically they found that a kdump kernel loaded anywhere < 4G worked, > the only change that was needed was to relaxy the 896M hard code. > > In one test they had a kdump kernel loaded above 2G. > Seriously, any case where we can't load anywhere in physical ram on x86-64 is a bug. i386 is another matter. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- 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/