Re: [PATCH vfs-2.6:for-next] vfs: remount_fs BKL pushdown

Christoph Hellwig
2009-05-06T06:26:50Z

On Wed, May 06, 2009 at 04:51:38AM +0100, Al Viro wrote:
> Actually, I'm not sure that you are right. Especially if we go for your
> "always hold s_umount for sync_filesystem()"; in that case we are guaranteed
> that we'll have an exclusion between ->write_super() and that sucker, so
> there's no reason to push it down into filesystems that do not use lock_super()

The interesting cases are locking against internal s_lock which at least
extN needs or ->write_super. And I'd really be rather safe than sorry
and audit individual filesystems than introducing bug in an obscure one.