GRUB doesn't boot all kernels

[Ralf Mardorf]

Hi,

for Wily and Arch Linux I build 3.10.61-rt65 and was able to boot it.
Now I build it for Xenial, too, no errors during building it, packages
could be installed without issues.
If I try to boot it, GRUB claims to boot it, but then just a flashing
cursor is shown and nothing else happens.
Journalctl only shows information related to 3.10.61-rt65 used with Wily [1],
today's trials to boot the new compiled 3.10.61-rt65 Xenial build are not
mentioned.
FWIW, I also re-installed grub [2] and let Xenial generate a grub.cfg [3],
with the automatically build grub.cfg, the last message shown by GRUB is
"Loading initial ramdisk..." and then it shows a not flashing cursor and
hangs.
Booting 4.4.0-28-lowlatency, x86_64 from official repositories works.

Is there a way to get a log file about what is going on?
I'll try recovery mode later today.

Regards,
Ralf

[1]
[root at moonstudio weremouse]# journalctl | grep rt65 | tail -n3
Mar 18 19:58:54 moonstudio kernel: Linux version 3.10.61-rt65-1-moonstudio (root at moonstudio) (gcc version 5.2.1 20150808 (Ubuntu 5.2.1-15ubuntu1) ) #1 SMP PREEMPT RT Sun Aug 23 02:13:10 CEST 2015
Mar 18 19:58:54 moonstudio kernel: Command line: BOOT_IMAGE=/boot/vmlinuz-3.10.61-rt65-1-moonstudio root=UUID=f705d2d5-0c6a-4338-8435-1bb56d7b6b19 ro
Mar 18 19:58:54 moonstudio kernel: Kernel command line: BOOT_IMAGE=/boot/vmlinuz-3.10.61-rt65-1-moonstudio root=UUID=f705d2d5-0c6a-4338-8435-1bb56d7b6b19 ro

[2]
[root at moonstudio weremouse]# grub-install /dev/sda 
Installing for i386-pc platform.
Installation finished. No error reported.
[root at moonstudio weremouse]# echo $?
0
[root at moonstudio weremouse]# /mnt/archlinux/bin/bootinfoscript /tmp/boot.txt 

Boot Info Script 0.61      [1 April 2012]
[snip]
[root at moonstudio weremouse]# grep Grub2 -A2 /tmp/boot.txt 
 => Grub2 (v1.99) is installed in the MBR of /dev/sda and looks at sector 1 of 
    the same hard drive for core.img. core.img is at this location and looks 
    in partition 97 for .

[3]
[root at moonstudio weremouse]# grub-mkconfig -o /boot/grub/grub.cfg 
[snip]
Found linux image: /boot/vmlinuz-3.10.61-rt65-1-moonstudio
Found initrd image: /boot/initrd.img-3.10.61-rt65-1-moonstudio
[snip]
done
[root at moonstudio weremouse]# echo $?
0