Comment 13 for bug 1659618

[Regression testing on Xenial AMD64]
AMD64 kernel already has kexec support on Xenial. The attached patch applies cleanly and builds on AMD64: https://pastebin.ubuntu.com/23950437/

== Installed kexec-tools built with ARM64 enablement patches ==
ubuntu@test:~$ dpkg -l | grep kexec-tools
ii kexec-tools 1:2.0.10-1ubuntu2.1 amd64 tools to support fast kexec reboots
ubuntu@test:~$

== Load kexec kernel and initiate kexec ==
ubuntu@test:~$ sudo kexec -l /boot/vmlinuz-4.4.0-62-generic --initrd=/boot/initrd.img-4.4.0-62-generic --append="root=LABEL=cloudimg-rootfs ro console=ttyS0"
ubuntu@test:~$ sudo kexec -e

== Successfully live booted kernel ==
Ubuntu 16.04.1 LTS test ttyS0

test login: [ 18.860792] kexec_core: Starting new kernel
[ 0.000000] Initializing cgroup subsys cpuset
[ 0.000000] Initializing cgroup subsys cpu
[ 0.000000] Initializing cgroup subsys cpuacct
[ 0.000000] Linux version 4.4.0-62-generic (buildd@lcy01-30) (gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.4) ) #83-Ubuntu SMP Wed Jan 18 14:10:15 UTC 2017 (Ubuntu 4.4.0-62.83-generic 4.4.40)
[ 0.000000] Command line: root=LABEL=cloudimg-rootfs ro console=ttyS0
[ 0.000000] KERNEL supported cpus:
[ 0.000000] Intel GenuineIntel
[ 0.000000] AMD AuthenticAMD
[ 0.000000] Centaur CentaurHauls
[ 0.000000] x86/fpu: Legacy x87 FPU detected.
[ 0.000000] x86/fpu: Using 'lazy' FPU context switches.
[ 0.000000] e820: BIOS-provided physical RAM map: