# Re: BUG: Mount ignores mount options

- From: David Howells \<dhowells@redhat.com\>
- Date: 2018-08-10 18:24:29 
- List: linux-api
- Page: https://ratatoskr.run/linux-api/2018/08/141840
- Thread: https://ratatoskr.run/linux-api/2018/08/141849/t.md

```text
Theodore Y. Ts'o [ref] wrote:

> Even *with* file system support, there's no way today for the VFS to
> keep track of whether a pathname resolution came through one
> mountpoint or another, so I can't do something like this:

Ummm...  Isn't that encoded in the vfsmount pointer in struct path?

However, the case folding stuff - is that a superblockism of a mountpointism?

> So if the file system has been mounted with one set of mount options,
> and you want to try to mount it with a conflicting set of mount
> options and you don't want it to silently ignore the mount options,
> the *only* thing we can today is to refuse the mount and return an
> error.  

With fsopen() there is the option to have the filesystem and the LSM attempt
to compare the non-key[*] mount options and reject the attempt to share if
they differ in any way.

David


[*] sget lookup keys, that is.
```