[Crash-utility] problems running crash on recent rawhide live kernels

[Dave Anderson]

 > Jeff Layton wrote:
 > > Relevant packages:
 > >
 > >     kernel-2.6.24-0.62.rc3.git5.fc9.x86_64
 > >     kernel-debuginfo-2.6.24-0.62.rc3.git5.fc9.x86_64
 > >     crash-4.0-4.10.x86_64
 > >
 > > ... the host is a FV xen guest (but that shouldn't matter, should
 > > it?).

To get crash version 4.0-4.11 to run against that particular
dumpfile, it needs to know the kernel's "phys_base" relocation
value.  And I don't know how (or if it's even possible) to get
it from a fully-virtualized Xen guest dumpfile.  However, if
you run crash on the live on the kernel that panicked, you can
determine it.  So running live on kernel-2.6.24-0.62.rc3.git5.fc9
I see:

   crash> help -m | grep phys_base
                   phys_base: ffffffffff200000
   crash>

...which in turn can be used as a command line argument for the
xendump dumpfile from that kernel.  So taking the sample dumpfile
you gave me:

# crash --machdep phys_base=0xffffffffff200000 vmlinux vmcore-rawhide.xmdump

crash 4.0-4.11
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, 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.

NOTE: setting phys_base to: 0xffffffffff200000

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: vmlinux
     DUMPFILE: vmcore-rawhide.xmdump
         CPUS: 1
         DATE: Tue Dec  4 15:41:08 2007
       UPTIME: 06:10:51
LOAD AVERAGE: 0.00, 0.00, 0.00
        TASKS: 74
     NODENAME: dhcp231-229.rdu.redhat.com
      RELEASE: 2.6.24-0.62.rc3.git5.fc9
      VERSION: #1 SMP Sat Dec 1 13:59:08 EST 2007
      MACHINE: x86_64  (3458 Mhz)
       MEMORY: 511.6 MB
        PANIC: "SysRq : Trigger a crashdump"
          PID: 0
      COMMAND: "swapper"
         TASK: ffffffff813a1780  [THREAD_INFO: ffffffff81496000]
          CPU: 0
        STATE: TASK_RUNNING (ACTIVE)

crash>

Pain in the ass.  But I don't know any better way.

Dave