Re: custom kernel without initrd and with udev

[Dom <toyer@rpdom.net>]

On 07/07/12 16:46, Mike McClain wrote:
> Hi Dom,
>
>
>      Thanks for your suggestions and letting me know this is still possible.
>
> On Sat, Jul 07, 2012 at 04:56:10AM +0100, Dom wrote:
> > On 07/07/12 00:08, Mike McClain wrote:
> <snip>
> > >      Is anyone running a custom kernel without an initrd with udev?
> >
> > Yes, I am. Although I believe there are some circumstances where
> > this may not be possible. eg. where something else needs to be
> > started in order to mount the root filesystem first.
>
> How do you get around the fact that udev is not running yet?
> May I see what your entry in grub.cfg looks like for this kernel?

By using the device name, rather than UUID or Label, it seems.

grub.cfg (for grub2) is:

#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
  load_env
fi
set default="0"
if [ "${prev_saved_entry}" ]; then
  set saved_entry="${prev_saved_entry}"
  save_env saved_entry
  set prev_saved_entry=
  save_env prev_saved_entry
  set boot_once=true
fi

function savedefault {
  if [ -z "${boot_once}" ]; then
    saved_entry="${chosen}"
    save_env saved_entry
  fi
}

function load_video {
  insmod vbe
  insmod vga
  insmod video_bochs
  insmod video_cirrus
}

insmod part_msdos
insmod ext2
set root='(hd0,msdos1)'
search --no-floppy --fs-uuid --set=root bad6c13d-19f0-47ad-bc6e-542a911d4178
if loadfont /usr/share/grub/unicode.pf2 ; then
  set gfxmode=800x480x24
  load_video
  insmod gfxterm
  insmod part_msdos
  insmod ext2
  set root='(hd0,msdos1)'
  search --no-floppy --fs-uuid --set=root 
bad6c13d-19f0-47ad-bc6e-542a911d4178
  set locale_dir=($root)/boot/grub/locale
  set lang=en_GB
  insmod gettext
fi
terminal_output gfxterm
set timeout=5
play 480 440 1
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=cyan/blue
set menu_color_highlight=white/blue
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux ###
menuentry 'Debian GNU/Linux, with Linux 3.2.19.libby2-586' --class 
debian --class gnu-linux --class gnu --class os {
	load_video
	set gfxpayload=keep
	insmod gzio
	insmod part_msdos
	insmod ext2
	set root='(hd0,msdos1)'
	search --no-floppy --fs-uuid --set=root 
bad6c13d-19f0-47ad-bc6e-542a911d4178
	echo	'Loading Linux 3.2.19.libby2-586 ...'
	linux	/boot/vmlinuz-3.2.19.libby2-586 root=/dev/hda1 ro  quiet noapm
}

(irrelevant bits trimmed)
--
Dom