[uml-user] No init found - Why?

[Itai T. <it...@ac...>]

Hi,

I'm new to UML.
I'm trying to run it with a very simple root directory mounted through
hostfs. I started out like so:

$ mkdir root
$ mkdir root/dev
$ mkdir root/sbin
$ cp /sbin/init root/sbin/init
$ linux ubd0=root

I expected this simple setup to get init started in the VM (without finding
inittab, obviously). but it doesn't work, the kernel seems to start
normally, but then says:

Kernel panic: No init found.  Try passing init= option to kernel.

Why is that?

My host is a RH-7.2 and my UML is 2.4.18.26um-0.

Thanks,
  -Itai