Comment 2 for bug 1850540

I've nominated mdadm for this issue as well because it currently does not:
  1) Let you create a new raid0 array w/o first setting a default_layout, which will regress behavior in installers, etc.
  2) save the layout version in the raid config, so you need to set default_layout - or set individual array layouts via sysfs - on every boot
  3) doesn't allow you to specify a layout when creating a raid0 (--layout is permitted for raid5, but not for raid0 yet)