A couple other things I should have mentioned with respect to your validity tests: ----- Original Message ----- > [root@kvm7 127.0.0.1-2014-02-07-19:17:09]# crash > /boot/System.map-2.6.32-220.el6.x86_64.debug > /usr/lib/debug/lib/modules/2.6.32-220.el6.x86_64.debug/vmlinux vmcore > > crash 5.1.8-1.el6 > Copyright (C) 2002-2011 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, 2007 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 (GDB) 7.0 > Copyright (C) 2009 Free Software Foundation, Inc. > License GPLv3+: GNU GPL version 3 or later < http://gnu.org/licenses/gpl.html > > > This is free software: you are free to change and redistribute it. > There is NO WARRANTY, to the extent permitted by law. Type "show copying" > and "show warranty" for details. > This GDB was configured as "x86_64-unknown-linux-gnu"... > > crash: page excluded: kernel virtual address: ffffffff81542000 type: > "cpu_possible_mask" > > I can go into minimal, Yes, but you didn't indicate whether data that is readable in the --minimal mode is meaningful. The best way to do that is to verify that you can read the linux_banner string at the advertised address, for example: crash> rd -a linux_banner 100 ffffffff81600020: Linux version 2.6.32-313.el6.x86_64 (mockbuild@x86-022.build ffffffff8160005c: .eng.bos.redhat.com) (gcc version 4.4.6 crash> If the command above doesn't show the "Linux ..." string lined up, you've got the wrong vmlinux. > > nm -Bn /usr/lib/debug/lib/modules/2.6.32-220.el6.x86_64.debug/vmlinux | grep _stext > ffffffff81000198 T _stext > > cat /proc/kallsyms | grep _stext > ffffffff81000198 T _stext That's not a valid test. The "_stext" symbol for both the standard kernel and the debug kernel variant both have the same "_stext" offset, but the symbols become rapidly out of sync afterwards. This is from the standard kernel's vmlinux file: $ nm -Bn vmlinux | grep -e _stext -e linux_banner ffffffff81000198 T _stext ffffffff81600020 R linux_banner $ as compared to the debug variant's vmlinux file: $ nm -Bn vmlinux.debug | grep -e _stext -e linux_banner ffffffff81000198 T _stext ffffffff8152e020 R linux_banner $ Dave -- Crash-utility mailing list Crash-utility@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/crash-utility