Subject: Re: mount_null: /mnt (/mnt) and /mnt are not distinct paths
To: Konrad Schroder <perseant@hitl.washington.edu>
From: Bill Studenmund <wrstuden@nas.nasa.gov>
List: tech-kern
Date: 06/29/1999 17:22:51
On Tue, 29 Jun 1999, Konrad Schroder wrote:

> Is there any reason why the various layered filesystems shouldn't be
> allowed to mount in-place?  The only current problem seems to be that
> lookup() holds the lock on the underlying directory when traversing a
> mount point, which it doesn't need to AFAICT ... 

While I have fussy ideas about the difference between mounts-in-place and
mounts-elsewhere fs's, we'll need this patch irregardless. :-)

I think it would be good to adjust mount_null so that it forbids

mount_null /foo /foo/bar      (or /foo /foo/bar/baz, etc).

I'm not sure how to do this in the kernel.

Take care,

Bill