shim-x64 の更新後、kdump サービスがメッセージ「kexec_file_load failed: Required key not available」を表示して起動に失敗する

Issue

• shim-x64 の更新後、kdump サービスがメッセージ「kexec_file_load failed: Required key not available」を表示して起動に失敗します。

# systemctl status kdump
● kdump.service - Crash recovery kernel arming
   Loaded: loaded (/usr/lib/systemd/system/kdump.service; enabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Tue 2020-08-04 23:31:46 IST; 5h 18min left
  Process: 1323 ExecStart=/usr/bin/kdumpctl start (code=exited, status=1/FAILURE)
 Main PID: 1323 (code=exited, status=1/FAILURE)

Aug 04 23:31:45 unused systemd[1]: Starting Crash recovery kernel arming...
Aug 04 23:31:46 unused kdumpctl[1323]: Secure Boot is enabled. Using kexec file based syscall.
Aug 04 23:31:46 unused kdumpctl[1323]: kexec_file_load failed: Required key not available
Aug 04 23:31:46 unused kdumpctl[1323]: kexec: failed to load kdump kernel
Aug 04 23:31:46 unused kdumpctl[1323]: Starting kdump: [FAILED]
Aug 04 23:31:46 unused systemd[1]: kdump.service: Main process exited, code=exited, status=1/FAILURE
Aug 04 23:31:46 unused systemd[1]: kdump.service: Failed with result 'exit-code'.
Aug 04 23:31:46 unused systemd[1]: Failed to start Crash recovery kernel arming.