From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758362Ab2CJEec (ORCPT ); Fri, 9 Mar 2012 23:34:32 -0500 Received: from mx1.redhat.com ([209.132.183.28]:64336 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757235Ab2CJEeb (ORCPT ); Fri, 9 Mar 2012 23:34:31 -0500 Message-ID: <4F5AD95C.5020209@redhat.com> Date: Sat, 10 Mar 2012 12:32:28 +0800 From: Dave Young User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.15) Gecko/20110323 Thunderbird/3.1.9 MIME-Version: 1.0 To: Cong Wang CC: linux-kernel@vger.kernel.org, x86@kernel.org, linux@arm.linux.org.uk, vgoyal@redhat.com Subject: Re: [PATCH] kdump x86: fix total mem size calculation for reservation References: <20120309083009.GA14067@darkstar.nay.redhat.com> <4F5ACA2D.5000000@gmail.com> In-Reply-To: <4F5ACA2D.5000000@gmail.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 On 03/10/2012 11:27 AM, Cong Wang wrote: > On 03/09/2012 04:30 PM, Dave Young wrote: >> crashkernel reservation need know the total memory size. Current >> get_total_mem >> simply use max_pfn - min_low_pfn. It is wrong because it will including >> memory holes in the middle. >> >> Especially for kvm guest with memory> 0xe0000000, there's below in >> qemu code: >> qemu split memory as below: >> if (ram_size>= 0xe0000000 ) { >> above_4g_mem_size = ram_size - 0xe0000000; >> below_4g_mem_size = 0xe0000000; >> } else { >> below_4g_mem_size = ram_size; >> } >> So for 4G mem guest, seabios will insert a 512M usable region beyond >> of 4G. >> Thus in above case max_pfn - min_low_pfn will be more than original >> memsize. >> >> Fixing this issue by using memblock_phys_mem_size() to get the total >> memsize. >> > > Makes sense for me! > >> -static inline unsigned long long get_total_mem(void) >> -{ >> - unsigned long long total; >> - >> - total = max_pfn - min_low_pfn; >> - printk("hidave: memsize=%llu\n", memblock_phys_mem_size()); > > This debugging line does not exist... so this patch can't be applied. Yes, good catch, will remove the line and resend. -- Thanks Dave