Chainloading on a LibreBoot X200

[Eduardo Ochs]

Hi List,

I have a LibreBoot X200 - with its Grub in flash memory updated to the
version from 20160907 - and I am not being able to make it boot a
bootable pen drive by chainloading. Let me tell the whole story.

I built the pen drive using live-build and this script (sorry for the
format!):

  http://angg.twu.net/e/live.e.html#live-build-chrome

The pen drive boots fine in my neighbor's computer, but when I try to
make the grub from flash memory boot it by doing something like this
(note: I tried several devices),

  set root=(usb0)
  chainloader +1
  boot

I get the error "unrecognised payload type"... I tried to add these
commands,

  insmod chain
  insmod ntfs
  insmod ext2

but nothing changed; and I also tried to install a more recent grub in
/dev/sda6 and chainload to it; grub is version
"2.02~beta2-9ubuntu1.14+7.0trisquel5" here, and /dev/sda6 is my root
partition nowadays (it is ext4). I tried this,

  sudo grub-install -v /dev/sda6

which gave this error:

  Embedding is not possible. GRUB can only be installed in this setup
  by using blocklists. However, blocklists are UNRELIABLE and their
  use is discouraged.

Then I tried this,

  sudo grub-install -v --force /dev/sda6

and checked the installation with bootinfoscript, who said:

  sda6: __________________________________________

    File system:       ext4
    Boot sector type:  Grub2 (v1.99)
    Boot sector info:  Grub2 (v1.99) is installed in the boot sector of
sda6
                       and looks at sector 102116496 of the same hard drive
                       for core.img. core.img is at this location and looks
                       in partition 112 for .
    Operating System:  Trisquel GNU/Linux 7.0
    Boot files:        /boot/grub/grub.cfg /etc/fstab

but when I try to chainload from the grub from flash memory to
/dev/sda6 by doing something like this,

  insmod chain
  insmod ntfs
  insmod ext2
  set root=(ahci0,6)
  chainloader +1
  boot

I also get the error "unrecognised payload type", plus "you need to
load the kernel first"...

Any hints? I really hope I'm missing something trivial...

  Cheers,
    Eduardo Ochs
    http://angg.twu.net/