[Crash-utility] crash-utility parse ramdump of arm64 failed

[Dave Anderson]

----- Original Message -----
> when I use the crash tool to analysis the ram dump of arm64,it failed，is
> someone can help me？the error information as follow。
> ----------------------------------------------------------------------------
> Port_COM151$ crash64 vmlinux
> DDRCS0_0.BIN at 0x00000000e0000000,DDRCS1_0.BIN at 0x0000000080000000
> crash64 7.1.9
> Copyright (C) 2002-2016 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.
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> and "show warranty" for details.
> This GDB was configured as "--host=x86_64-unknown-linux-gnu
> --target=aarch64-elf-linux"...
> 
> crash64: read error: kernel virtual address: ffffff8ed5cccef0 type:
> "possible"
> WARNING: cannot read cpu_possible_map
> crash64: read error: kernel virtual address: ffffff8ed5cccee8 type: "present"
> WARNING: cannot read cpu_present_map
> crash64: read error: kernel virtual address: ffffff8ed5ccced8 type: "online"
> WARNING: cannot read cpu_online_map
> crash64: read error: kernel virtual address: ffffff8ed5cccef8 type: "active"
> WARNING: cannot read cpu_active_map
> crash64: read error: kernel virtual address: ffffff8ed5cccee8 type:
> "cpu_present_map"
> crash64: read error: kernel virtual address: ffffff8ed5ccced8 type:
> "cpu_online_map"
> crash64: read error: kernel virtual address: ffffff8ed5ccced8 type:
> "cpu_online_map"
> crash64: read error: kernel virtual address: ffffff8ed5ccced8 type:
> "cpu_online_map"
> Segmentation fault (core dumped)
> 
>

I am not very familiar with ARM64 ramdumps, but if you display the output of 
"crash -d4 vmlinux DDRCS0_0.BIN at 0x00000000e0000000,DDRCS1_0.BIN at 0x0000000080000000",
there may be something more useful.  (or even "crash -d8 ...").  My guess is that it needs
the value of "kimage_voffset", which is normally found in the VMCOREINFO data and which
doesn't exist in ramdumps.  Or maybe it's not calculating the correct "phys_offset" value.
Both of them can be manually applied with the "crash --machdep" command line option, but
you would need to know what the values were on the crashed system.

Perhaps the authors of the crash utility's ramdump support may have other suggestions.

Dave