Comment 12 for bug 1410604

Booting with "debug=y" works better, as then the initramfs debug goes right on the console, instead of /run/initramfs/initramfs.debug. This shows that even the initrd starts after the error message, so this must come from the kernel itself:

Loading Linux 4.4.0-8-generic ...
Loading initial ramdisk ...
OF stdout device is: /vdevice/vty@30000000
Preparing to boot Linux version 4.4.0-8-generic (buildd@bos01-ppc64el-008) (gcc version 5.3.1 20160222 (Ubuntu/IBM 5.3.1-9ubuntu3) ) #23-Ubuntu SMP Wed Feb 24 20:43:54 UTC 2016 (Ubuntu 4.4.0-8.23-generic 4.4.2)
Detected machine type: 0000000000000101
Max number of cores passed to firmware: 2048 (NR_CPUS = 2048)
Calling ibm,client-architecture-support... done
command line: BOOT_IMAGE=/boot/vmlinux-4.4.0-8-generic root=UUID=9f6cb10b-904a-4b22-b9e1-80455f176cc2 ro console=hvc0 earlyprintk debug=y
memory layout at init:
  memory_limit : 0000000000000000 (16 MB aligned)
  alloc_bottom : 0000000005860000
  alloc_top : 0000000030000000
  alloc_top_hi : 0000000080000000
  rmo_top : 0000000030000000
  ram_top : 0000000080000000
instantiating rtas at 0x000000002fff0000... done
prom_hold_cpus: skipped
copying OF device tree...
Building dt strings...
Building dt structure...
Device tree strings 0x0000000005870000 -> 0x0000000005870849
Device tree struct 0x0000000005880000 -> 0x0000000005890000
Quiescing Open Firmware ...
Booting Linux via __start() ...
[ 0.000000] Allocated 4980736 bytes for 2048 pacas at c00000000fb40000
[ 0.000000] Using pSeries machine description

[... only kernel messages here ...]

[ 0.633920] hctosys: unable to open rtc device (rtc0)
[ 0.634546] Freeing unused kernel memory: 6144K (c000000000e80000 - c000000001480000)
Loading, please wait...
+ [ -z ]
+ BOOT=local
+ [ -n ]
+ resume=
+ maybe_break top
+ export BOOT
+ run_scripts /scripts/init-top