Bug#848945: #848945 Empty rpool leaves ZFS systems unbootable

[Etienne Dechamps]

By the way, for those who don't like patching packaged files, here's a
workaround for manually overriding the root= parameter from
/etc/default/grub:

GRUB_FS=manual
GRUB_DISABLE_LINUX_UUID=true
GRUB_DEVICE=ZFS=yourpoolname/path/to/your/root/dataset