This patch is from Olaf Hering.

The rtas property 'ibm,os-term' is not available on JS20, a panic will print:

unable to mount root filesystem on /dev/hda
Kernel panic - not syncing: Attempted to kill init!
 <0>ibm,os-term call failed -1
Rebooting in 42 seconds..
Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>