Bug#586985: [grub-common] Regression: grub-probe fails

[Colin Watson]

On Thu, Jun 24, 2010 at 12:01:40PM +0200, Peter Fritzsche wrote:
> Unpacking replacement memtest86+ ...
> /usr/sbin/grub-probe: error: cannot find a device for / (is /dev mounted?).
[...]
> I have a relative simple setup.There is a sda and sdb. sda has sda1 which is 
> /boot and sda2 which is crypted and then part one of an lvm. sdb1 has only 
> crypted and then part 2 of the lvm. Inside the lvm is a "root-lvm" which is / 
> and a swap partition.

Sounds like #542165, or possibly #550704.  Could you please try the
version of grub-common and grub-pc in unstable?

If that doesn't help, please show me the output of:

  cat /boot/grub/device.map
  sh -x /usr/sbin/grub-mkconfig -o /boot/grub/grub.cfg

> So first thing: I don't understand why grub should be interested in my / ... 
> there is a /boot mounted.

In general (although perhaps not in every specific case), GRUB still
needs to know things about /; for example, update-grub needs to generate
appropriate root= kernel parameters.

-- 
Colin Watson                                       [cjwatson at debian.org]