Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755523Ab0LQUBy (ORCPT ); Fri, 17 Dec 2010 15:01:54 -0500 Received: from mx1.redhat.com ([209.132.183.28]:12577 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752640Ab0LQUBx (ORCPT ); Fri, 17 Dec 2010 15:01:53 -0500 Date: Fri, 17 Dec 2010 15:01:39 -0500 From: Vivek Goyal To: Yinghai Lu Cc: "H. Peter Anvin" , Stanislaw Gruszka , Ingo Molnar , Thomas Gleixner , Maxim Uvarov , "linux-kernel@vger.kernel.org" , Neil Horman Subject: Re: kdump broken on 2.6.37-rc4 Message-ID: <20101217200139.GF14502@redhat.com> References: <4D0AD976.3020504@zytor.com> <3C6B7683-9CDC-4C4A-A32A-56227DE01387@kernel.org> <20101217170146.GC9568@redhat.com> <4D0BA45A.7020402@zytor.com> <20101217180242.GB12425@redhat.com> <4D0BAA24.3080801@kernel.org> <4D0BBC55.4010207@zytor.com> <4D0BBE00.3010602@kernel.org> <20101217195035.GE14502@redhat.com> <4D0BBF6B.4060105@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4D0BBF6B.4060105@kernel.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2068 Lines: 65 On Fri, Dec 17, 2010 at 11:52:11AM -0800, Yinghai Lu wrote: > On 12/17/2010 11:50 AM, Vivek Goyal wrote: > > On Fri, Dec 17, 2010 at 11:46:08AM -0800, Yinghai Lu wrote: > >> On 12/17/2010 11:39 AM, H. Peter Anvin wrote: > >>> On 12/17/2010 10:21 AM, Yinghai Lu wrote: > >>>>>> > >>>>>> Do we have actual testing for how high the 64-bit kernel will load? > >>>>> > >>>>> I will do some experiments on my box today and let you know. > >>>> > >>>> if bzImage is used, it is 896M. > >>>> > >>> > >>> Why? 896 MiB is a 32-bit kernel limitation which doesn't have anything > >>> to do with the bzImage format. > >>> > >>> So unless there is something going on here, I suspect you're just plain > >>> flat wrong. > >> > >> kexec-tools have some checking when it loads bzImage. > >> > > > > Yinghai, > > > > I think x86_64 might have just inherited the settings of 32bit without > > giving it too much of thought. At that point of time nobody bothered > > to load the kernel from high addresses. So these might be artificial > > limits. > > good point. will check that. Yinghai, On x86_64, I am not seeing "Crash kernel" entry in /proc/iomem. I see following in dmesg. "[ 0.000000] Reserving 128MB of memory at 64MB for crashkernel (System RAM: 5120MB)" Following is my /proc/iomem. # cat /proc/iomem 00000100-0000ffff : reserved 00010000-00096fff : System RAM 00097000-0009ffff : reserved 000c0000-000e7fff : pnp 00:0f 000e8000-000fffff : reserved 00100000-bffc283f : System RAM 01000000-015d1378 : Kernel code 015d1379-01aee00f : Kernel data 01bc8000-024b4c4f : Kernel bss bffc2840-bfffffff : reserved So there is RAM available at the requested address still no entry for "Crash Kernel". This is both with 2.6.36 as well as 37-rc6 kernel. I am wondering if insert_resource() is failing here? Thanks Vivek -- 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/