kexec does not appear to work

[Sebastian Unger]

I have been using kexec for quite some time on desktop and server Ubuntu installations. Recently I've started using Raspberry Pi 3's for some of the server tasks. Unfortunately I can't seem to get kexec working. I have searched but found no mention of similar problems nor any indication that kexec is simply not supported on the RPI3 (or on ARM in general).

My symptoms are that the kexec_load system call appears to return with EINVAL:

root@media2:~# kexec /boot/vmlinuz-4.4.0-1029-raspi2 --initrd /boot/initrd.img-4.4.0-1029-raspi2 --command-line "$(</proc/cmdline)"
Modified cmdline:8250.nr_uarts=1 dma.dmachans=0x7f35 bcm2708_fb.fbwidth=1824 bcm2708_fb.fbheight=984 bcm2709.boardrev=0xa22082 bcm2709.serial=0xyyyyyyyy smsc95xx.macaddr=XX:XX:XX:XX:XX:XX bcm2708_fb.fbswap=1 bcm2709.uart_clock=48000000 vc_mem.mem_base=0x3dc00000 vc_mem.mem_size=0x3f000000 root=/dev/vg0/root ro crashkernel=0M-:128M
Unable to find /proc/device-tree//chosen/linux,stdout-path, printing from purgatory is diabled
kexec_load failed: Invalid argument
entry = 0x8000 flags = 0x280000
nr_segments = 3
segment[0].buf = 0x76831008
segment[0].bufsz = 0x65b328
segment[0].mem = 0x8000
segment[0].memsz = 0x65c000
segment[1].buf = 0x75dc2008
segment[1].bufsz = 0xa6e714
segment[1].mem = 0x196d000
segment[1].memsz = 0xa6f000
segment[2].buf = 0x11a2410
segment[2].bufsz = 0x3c18
segment[2].mem = 0x23dc000
segment[2].memsz = 0x4000

This happens whether or not I put any crashkernel parameter on the kernel command-line used to boot the machine in the first place.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: linux-image-4.4.0-1029-raspi2 4.4.0-1029.36
ProcVersionSignature: Ubuntu 4.4.0-1029.36-raspi2 4.4.21
Uname: Linux 4.4.0-1029-raspi2 armv7l
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: armhf
Date: Mon Dec 5 22:25:17 2016
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_NZ.UTF-8
 SHELL=/bin/bash
SourcePackage: linux-raspi2
UpgradeStatus: No upgrade log present (probably fresh install)

[Sebastian Unger (sebunger44)]

Can somebody at least comment on whether this is expected?