Re: [PATCH 0/3] fanotify support for btrfs sub-volumes

Christoph Hellwig
2023-11-06T12:31:07Z

On Mon, Nov 06, 2023 at 11:59:22AM +0100, Christian Brauner wrote:
> > > They
> > > all know that btrfs subvolumes are special. They will need to know that
> > > btrfs subvolumes are special in the future even if they were vfsmounts.
> > > They would likely end up with another kind of confusion because suddenly
> > > vfsmounts have device numbers that aren't associated with the superblock
> > > that vfsmount belongs to.
> >
> > This looks like you are asking user space programs (especially legacy
> > ones) to do special handling for btrfs, which I don't believe is the
> > standard way.
>
> I think spending time engaging this claim isn't worth it. This is just
> easily falsifiable via a simple grep for btrfs in systemd, lxc, runc,
> util-linux.

Myabe you need to get our of your little bubble. There is plenty of
code outside the fast moving Linux Desktop and containers bubbles that
takes decades to adopt to new file systems, and then it'll take time
again to find bugs exposed by such odd behavior.