dbfdf6cb36
blockdev-add fails if an invalid node name is given, so we should document what a valid node name even is. Reported-by: Cong Li <coli@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Cong Li <coli@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com>