Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755377Ab0LQR53 (ORCPT ); Fri, 17 Dec 2010 12:57:29 -0500 Received: from terminus.zytor.com ([198.137.202.10]:48531 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755156Ab0LQR51 (ORCPT ); Fri, 17 Dec 2010 12:57:27 -0500 Message-ID: <4D0BA45A.7020402@zytor.com> Date: Fri, 17 Dec 2010 09:56:42 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc14 Thunderbird/3.1.7 MIME-Version: 1.0 To: Vivek Goyal CC: Yinghai , Stanislaw Gruszka , Ingo Molnar , Thomas Gleixner , Maxim Uvarov , "linux-kernel@vger.kernel.org" , Neil Horman Subject: Re: kdump broken on 2.6.37-rc4 References: <20101209124117.GA6032@redhat.com> <4D01377B.5070809@kernel.org> <20101213100848.GA2237@redhat.com> <4D0663F0.2060103@kernel.org> <4D06783C.6040009@zytor.com> <20101214224135.GB19693@redhat.com> <20101215103954.GA2243@redhat.com> <4D09958D.2040907@kernel.org> <4D0AD976.3020504@zytor.com> <3C6B7683-9CDC-4C4A-A32A-56227DE01387@kernel.org> <20101217170146.GC9568@redhat.com> In-Reply-To: <20101217170146.GC9568@redhat.com> 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 Content-Length: 1416 Lines: 33 On 12/17/2010 09:01 AM, Vivek Goyal wrote: > On Thu, Dec 16, 2010 at 07:58:48PM -0800, Yinghai wrote: >> Please don't do that to 64 bit >> >> My big system with 1024g memory and a lot of cards with rhel 6 to make kdump work must have crashkernel=512m and second kernel need to take pci=nomsi >> > > I agree here that we should not do it for 64 bit. > > - Just because we need it for 32 bit does not mean we should limit it for > 64bit. And we do want to have the capability to boot the kernel from as > high memory as possible so creating another aritificial limit is counter > to that. > > - I would not worry too much about backward compatibility and allow > booting 32bit kernel till 768MB. The reason being that most of the > distros use same kernel for crash dumping as regular kernel. Maintainig > two separate kernels is big hassle. > > So a small set of people who run into issue, would need to change kernel > command line "crashkernel=128M@64M" or something similar. > Do we have actual testing for how high the 64-bit kernel will load? I'm assuming that the usage of a 32-bit kdump kernel for a 64-bit main kernel is nonexistent. -hpa -- 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/