Bug#741342: /usr/sbin/update-grub: update-grub writes root=UUID= to grub.cfg for LVM2, renders machine unbootable

[Stefan Lippers-Hollmann]

Hi

While using UUIDs for lvm2 logical volumes works within grub2 itself, 
it does blow up in the initramfs integration hooks of lvm2:

http://anonscm.debian.org/viewvc/pkg-lvm/lvm2/trunk/debian/initramfs-tools/lvm2/scripts/local-top/lvm2?view=markup

[line 40ff]
	# Make sure that we have a d-m path
	dev="${dev#/dev/mapper/}"
	if [ "$dev" = "$1" ]; then
		return 1
	fi

so without a root=/dev/mapper/[...] definition for the rootfs, the 
default provider of linux-initramfs-tool in Debian never even tries 
to assemble the volume groups that make up the rootfs. Out of curiosity
I rigged that particular regexp to be always false, but lvm2 didn't 
manage to find a rootfs on a logical volume then either (complaining
that UUIDs were not valid for logical volumes).

Accordingly there would be several changes and versioned dependencies 
(Breaks) needed to the lvm2 initramfs-tools hooks, before using 
anything but /dev/mapper/... rootfs definitions might be viable for 
grub2.

Regards
	Stefan Lippers-Hollmann
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 836 bytes
Desc: This is a digitally signed message part.
URL: <http://lists.alioth.debian.org/pipermail/pkg-grub-devel/attachments/20140311/30cb6117/attachment.sig>