Re: [PATCH] private mounts

[Jamie Lokier <jamie@shareable.org>]

Miklos Szeredi wrote:
> > Actually, in terms of complexity, it's not much different from using
> > bind mounts.
> 
> As has been suggested by Pavel, bind mounting foreign namespaces could
> just be done with a new bind_fd(fd, path) syscall and file descriptor
> passing with SCM_RIGHTS.

Yes, he's right.

But you don't need a new system call to bind an fd.

"mount --bind /proc/self/fd/N mount_point" works, try it.

> That sounds to me orders of magnitude less complex (on the kernel side
> at least) than sb sharing.

In terms of what happens in the kernel, they're almost exactly the
same: either way, a super block ends up shared by two mounts.  That's
what I meant.

I agree that in terms of what userspace has to do, if just binding
works that's simpler.  And it does seem to work with the above mount
command.

-- Jamie