Re: [Crash-utility] crash: invalid kernel virtual address: 0 type: "memory section"

Just for sanity's sake, try this: $ ./crash --minimal ../ddeb/usr/lib/debug/boot/vmlinux-3.13.0-39-generic ../dump.201412280256 and see if you can read the linux_banner string successfully. For example, using my sample 3.13 kernel: $ crash --minimal 3.13.0-0.rc1.git2.1.fc20_SLAB/vmlinux.gz 3.13.0-0.rc1.git2.1.fc20_SLAB/vmcore_c_d31 crash 7.0.9 Copyright (C) 2002-2014 Red Hat, Inc. Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005, 2011 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) 7.6 Copyright (C) 2013 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"... NOTE: minimal mode commands: log, dis, rd, sym, eval, set, extend and exit crash> rd -a linux_banner ffffffff818000c0: Linux version 3.13.0-0.rc1.git2.1.fc20.x86_64 (root@hp-xw455 ffffffff818000fc: 0-02.ml3.eng.bos.redhat.com) (gcc version 4.8.1 20130814 (Re ffffffff81800138: d Hat 4.8.1-6) (GCC) ) #1 SMP Tue Nov 26 14:42:45 EST 2013 crash> And then try reading other stuff, most notably the __per_cpu_offset[] array, like this: crash> rd __per_cpu_offset 256