The pivot_root(2) man page says:
"new_root does not have to be a mount point."
But I couldn't get pivot_root(2) succeed unless new_root was a mount
point. So I dived into the Linux source and found the following comment
(in fs/namespace.c):
* - it's okay to pick a root that isn't the root of a file system, e.g.
* /nfs/my_root where /nfs is the mount point. It must be a mountpoint,
* though, so you may need to say mount --bind /nfs/my_root /nfs/my_root
* first.
So I think the man page is incorrect.
--
Jakub Wilk
