gpart destroy, zpool destroy, zfs destroy under securelevel 3

[Vladimir Sharun]

Hello,

> Ok, you are right. But geom_dev restricts access only from user level
> applications. When GEOM object does access directly via GEOM methods
> this protection won't work. And it seems it isn't easy to fix, all
> classes should have own check.

Thank you for better clarification. This is the goal I mentioned in
first email: GEOM & ZFS layers/subsystems are securelevel ignorant.