Re: trying to debug xen4 & qemu-dm, Xen reports "core dump failed"

[0bo0 <0.bugs.only.0@gmail.com>]

On Tue, Jan 26, 2010 at 2:30 PM, Keir Fraser <keir.fraser@eu.citrix.com> wrote:
>>> Now try starting your guest. It fails, and hopefully you have a core file in
>>> /var/core/. You can load it into gdb as 'gdb /usr/lib/xen/qemu-dm
>>> /var/core/name-of-core-file' and then execute bt command at the gdb prompt.
>>> That hopefully tells us where qemu-dm crashed.
>>
>> bash
>> ulimit -c unlimited
>
> Actually that probably only enable core dumps for the shell you are running.
> Qemu-dm will inherit its ulimits from xend. So you need to enable core dumps
> by running 'ulimit -c unlimited' before you start xend, or put it in the
> startup script that starts xend. You could also script the echo to
> /proc/sys/kernel/core_pattern, but it's definitely safe to do that later
> from a shall, as it's a global value, rather than per-process.

bash
ulimit -c unlimited
echo '/var/core/core.%e.%u.%p' > /proc/sys/kernel/core_pattern
mkdir -p /var/core
cat /proc/sys/kernel/core_pattern
/var/core/core.%e.%u.%p

service xend restart
xm create /etc/xen/vm/test.cfg
ls -al /var/core/ | grep core
  -rw-------  1 root root 4542464 2010-01-26 14:36 core.qemu-dm.0.7772

gdb /usr/lib64/xen/bin/qemu-dm /var/core/core.qemu-dm.0.7772
  ...
  /usr/lib64/xen/bin/qemu-dm: Too many levels of symbolic links.
  Missing separate debuginfo for the main executable file
  Try: zypper install -C
"debuginfo(build-id)=9326caa0db4accd719f10b02a9a41a40c10b662a"
  Core was generated by `/usr/lib/xen/bin/qemu-dm -d 4 -serial pty
-domain-name test -videoram 4 -k en-u'.
  Program terminated with signal 11, Segmentation fault.
  #0  0x000000000047b974 in ?? ()
  (gdb) quit

zypper install -C "debuginfo(build-id)=9326caa0db4accd719f10b02a9a41a40c10b662a"
  Loading repository data...
  Reading installed packages...
  'debuginfo(build-id)=9326caa0db4accd719f10b02a9a41a40c10b662a' not found.
  Resolving package dependencies...

so where/how do I get the debug symbols?