Re: [PATCH] sysv: Remove the filesystem

Christian Brauner
2025-01-09T15:05:17Z

On Wed, Jan 08, 2025 at 04:32:55PM -0600, Bill O'Donnell wrote:
> On Tue, Jan 07, 2025 at 03:35:35PM +0100, Christian Brauner wrote:
> > On Mon, Jan 06, 2025 at 05:24:01PM +0100, Jan Kara wrote:
> > > Since 2002 (change "Replace BKL for chain locking with sysvfs-private
> > > rwlock") the sysv filesystem was doing IO under a rwlock in its
> > > get_block() function (yes, a non-sleepable lock hold over a function
> > > used to read inode metadata for all reads and writes). Nobody noticed
> > > until syzbot in 2023 [1]. This shows nobody is using the filesystem.
> > > Just drop it.
> > >
> > > [1] https://lore.kernel.org/all/0000000000000ccf9a05ee84f5b0@google.com/
> > >
> > > Signed-off-by: Jan Kara <jack@suse.cz>
> > > ---
> > > What do people think about this? Or should we perhaps go through a (short)
> > > deprecation period where we warn about removal?
> >
> > Let's try and kill it. We can always put it back if we have to.
> >
> So should any work toward converting sysv to the new mount API stop? ;)

So I would suggest we try and remove it for v6.15. If the removal
survives the release of v6.16 I would call it a (qualified) success.

If during this time we find out that we have to keep it and have to
reintroduce it then we may as well spend the time to port it to the new
mount api.

Thoughts?