From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([66.187.233.31]) by canuck.infradead.org with esmtp (Exim 4.63 #1 (Red Hat Linux)) id 1IGH0b-00079W-F2 for kexec@lists.infradead.org; Wed, 01 Aug 2007 12:25:15 -0400 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.13.1/8.13.1) with ESMTP id l71GPBmN007584 for ; Wed, 1 Aug 2007 12:25:11 -0400 Received: from mail.boston.redhat.com (mail.boston.redhat.com [172.16.76.12]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id l71GPAuc019507 for ; Wed, 1 Aug 2007 12:25:11 -0400 Received: from redhat.com (crash.boston.redhat.com [172.16.80.17]) by mail.boston.redhat.com (8.13.1/8.13.1) with ESMTP id l71GPAsk031375 for ; Wed, 1 Aug 2007 12:25:10 -0400 Message-ID: <46B0B507.5090704@redhat.com> Date: Wed, 01 Aug 2007 12:29:59 -0400 From: Dave Anderson MIME-Version: 1.0 Subject: Question re: mem= usage and resultant vmcore List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org+dwmw2=infradead.org@lists.infradead.org To: kexec@lists.infradead.org On an 4GB x86_64 kernel, with memory restricted with "mem=" like so: kernel /vmlinuz-2.6.18-36.el5 ro root=/dev/VolGroup00/LogVol00 console=ttyS0,115200 mem=2000m crashkernel=128M@16M The secondary kernel boots fine with this: Kernel command line: ro root=/dev/VolGroup00/LogVol00 console=ttyS0,115200 mem=2000m irqpoll maxcpus=1 memmap=exactmap memmap=640K@0K memmap=5048K@16384K memmap=125368K@22072K elfcorehdr=147440K memmap=76K#3406720K memmap=564K#3406796K The /proc/vmcore shows 4GB: # ls -l /proc/vmcore -r-------- 1 root root 4164192032 Aug 1 10:57 /proc/vmcore # I'm not sure whether that's supposed to reflect the "mem=2000m" size or not? Anyway, when copied to /var/crash, the "cp" command in the kdump init file returns a 1, and the vmcore file is kept named as "vmcore-incomplete". But the vmcore-incomplete looks to be the "right" size, and is functional as a vmcore file: # crash /usr/lib/debug/lib/modules/2.6.18-36.el5/vmlinux vmcore-incomplete crash 4.0-4.3.1 Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007 Red Hat, Inc. Copyright (C) 2004, 2005, 2006 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005 NEC Corporation Copyright (C) 1999, 2002 Silicon Graphics, Inc. Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. This program is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Enter "help copying" to see the conditions. This program has absolutely no warranty. Enter "help warranty" for details. GNU gdb 6.1 Copyright 2004 Free Software Foundation, Inc. GDB is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Type "show copying" to see the conditions. There is absolutely no warranty for GDB. Type "show warranty" for details. This GDB was configured as "x86_64-unknown-linux-gnu"... KERNEL: /usr/lib/debug/lib/modules/2.6.18-36.el5/vmlinux DUMPFILE: vmcore-incomplete CPUS: 4 DATE: Wed Aug 1 11:47:13 2007 UPTIME: 00:02:15 LOAD AVERAGE: 0.16, 0.14, 0.06 TASKS: 118 NODENAME: nec-em17.rhts.boston.redhat.com RELEASE: 2.6.18-36.el5 VERSION: #1 SMP Fri Jul 20 14:26:46 EDT 2007 MACHINE: x86_64 (2992 Mhz) MEMORY: 1.9 GB PANIC: "SysRq : Trigger a crashdump" PID: 3044 COMMAND: "bash" TASK: ffff8100794f0100 [THREAD_INFO: ffff8100656dc000] CPU: 0 STATE: TASK_RUNNING (SYSRQ) crash> So two questions -- should the /proc/vmcore on the secondary kernel reflect the restricted size, and what would cause the "cp" to only copy the "correct" amount, while returning an error code? Dave _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec