Xen Kdump analysis with crash utility

[Ковалёв Сергей <valor@xxxxxxx>]

Hello,

I'm trying to start use of Kdump in my Xen 4.16 setup with Ubuntu 
18.04.6 ( 5.4.0-137-generic ).
I was able to load "dump-capture kernel" with kexec-tools and collect 
crashdump with makedumpfile like this:
```
makedumpfile -E -X -d 0 /proc/vmcore /var/crash/dump
```

This dump file could be used to analyze Dom0 panics.

Though I have some issues while analyzing dump file for Xen kernel:
```
 ~/src/crash/crash --hyper ~/xen-syms-dbg/usr/lib/debug/xen-syms 
/var/crash/202301241536/dump.202301241536
crash 8.0.2++
...
GNU gdb (GDB) 10.2
...
crash: invalid kernel virtual address: 1ef8  type: "fill_pcpu_struct"
WARNING: cannot fill pcpu_struct.

crash: cannot read cpu_info.
```

As far as I know developers community of crash utility doesn't actively 
support Xen. From 
https://github.com/crash-utility/crash/issues/21#issuecomment-330847410 :
```
I cannot help you with Xen-related issues because Red Hat stopped releasing
Xen kernels several years ago (RHEL5 was the last Red Hat kernel that 
contained
a Xen kernel).  Since then, ongoing Xen kernel support in the crash utility
has been maintained by engineers who work for other distributions that still
offer Xen kernels.
```

Does anybody use kdump to analyze Xen crashes? Could anybody share some 
tips and tricks with me to use crash or other tools with such dumps?
Thanks a lot.
--
Best regards,
Sergey Kovalev