Bugreport by Tong Sun:

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I found that the bootfrom=xxx.iso cheatcode does not work as expected.

I notice the following grub boot menu,

title           GRML 0.9 from .ISO on sda2
  root          (hd0,2)
  kernel  /boot.grml/isolinux/linux26 welcome noeject noprompt
ramdisk_size=100000 init=/etc/init lang=us apm=power-off vga=791 nomce
bootfrom=/dev/sda2/Grml/grml_0.9.iso
  initrd  /boot.grml/isolinux/minirt26.gz
  savedefault
  boot

only works as long as my USB key was plugged in. If not, it won't work.

Having Looked into the issue, I realized that,

grml search for grml image in all patitions first before doing the bootfrom=
cheatcode. When my USB key is plugged in, it can continue on, mounting the .iso
as root the second time, though it report missing /lib/.../modeprobe.dep
beforehand.

When my USB key is not plugged in, i.e., the image scan doesn't find anything,
grml will panic before doing the bootfrom=xxx.iso.

Test environment: grml 0.9
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