kdump service failed in IMA appraisal enforce mode, the error message in dmesg is (dmesg | grep appraise):

[ 2.999327] audit: type=1800 audit(1602644578.504:2): pid=145 uid=0 auid=4294967295 ses=4294967295 subjnel op=appraise_data cause=unknown comm="kworker/u8:0" name="/usr/bin/kmod" dev="rootfs" ino=10402 res=0
[ 15.514744] ima: impossible to appraise a kernel image without a file descriptor; try using kexec_file_ syscall.

The error message in kernel is (journalctl -u kdump):

Oct 14 11:03:07 localhost.localdomain systemd[1]: Starting Crash recovery kernel arming...
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: kexec_load failed: Permission denied
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: entry = 0xe22ab6b0 flags = 0xb70001
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: nr_segments = 5
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[0].buf = 0xffff9e8ef010
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[0].bufsz = 0x136ad40
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[0].mem = 0xdfe80000
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[0].memsz = 0x15c1000
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[1].buf = 0xffffa1a6f010
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[1].bufsz = 0xe682f3
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[1].mem = 0xe1441000
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[1].memsz = 0xe69000
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[2].buf = 0xaaaaed7e44d0
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[2].bufsz = 0x4f1
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[2].mem = 0xe22aa000
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[2].memsz = 0x1000
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[3].buf = 0xaaaaed7e4fc0
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[3].bufsz = 0x34a8
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[3].mem = 0xe22ab000
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[3].memsz = 0x4000
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[4].buf = 0xaaaaed7e2850
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[4].bufsz = 0x400
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[4].mem = 0xffdff000
Oct 14 11:03:11 localhost.localdomain kdumpctl[2493]: segment[4].memsz = 0x1000
Oct 14 11:03:11 localhost.localdomain kdumpctl[1928]: kexec: failed to load kdump kernel
Oct 14 11:03:11 localhost.localdomain kdumpctl[1928]: Starting kdump: [FAILED]
Oct 14 11:03:11 localhost.localdomain systemd[1]: kdump.service: Main process exited, code=exited, statu>
Oct 14 11:03:11 localhost.localdomain systemd[1]: kdump.service: Failed with result 'exit-code'.
Oct 14 11:03:11 localhost.localdomain systemd[1]: Failed to start Crash recovery kernel arming.