root@armadillo:/home/atmark# kdump-config unload
[ ok ] unloaded kdump kernel.
root@armadillo:/home/atmark# kdump-config load
[FAIL] Invalid kernel version : 4.9.133-at25 ... failed!
syscall kexec_file_load not available.
[ ok ] loaded kdump kernel.

root@armadillo:/home/atmark# kdump-config test
USE_KDUMP:         1
KDUMP_SYSCTL:      kernel.panic_on_oops=1
KDUMP_COREDIR:     /var/crash
crashkernel addr:  0x98000000
kdump kernel addr:
kdump kernel:
   /home/atmark/linux_at25/zImage
kdump initrd:

kexec command to be used:
  /sbin/kexec -p --command-line="console=ttymxc4,115200 root=/dev/mmcblk2p2 rootwait rw nr_cpus=1 systemd.unit=kdump-tools.service irqpoll nousb ata_piix.prefer_ms_hyperv=0 crashkernel=192M" /home/atmark/linux_at25/zImage

root@armadillo:/home/atmark# kdump-config savecore
[info] running makedumpfile -d 31 --message-level 1 /proc/vmcore /var/crash/202211140912/dump-incomplete.
[FAIL] kdump-config: makedumpfile failed, falling back to 'cp' ... failed!
cp: '/proc/vmcore' を stat できません: そのようなファイルやディレクトリはありません
[FAIL] kdump-config: failed to save vmcore in /var/crash/202211140912 ... failed!
[info] running makedumpfile --dump-dmesg /proc/vmcore /var/crash/202211140912/dmesg.202211140912.
open_dump_memory: Can't open the dump memory(/proc/vmcore). No such file or directory

makedumpfile Failed.
[FAIL] kdump-config: makedumpfile --dump-dmesg failed. dmesg content will be unavailable ... failed!
[FAIL] kdump-config: failed to save dmesg content in /var/crash/202211140912 ... failed!