On Mon, 18 Nov 1996, Jukka Marin wrote:

> Someone mentioned that unionfs is broken and doesn't work in all
> circumstances.  Is it safe to use it to mount a local disk over an NFS
> mounted disk for kernel/userland builds?  I'm running pre-1.2 -current
> and 1.2 on my machines at the moment.

I've been using unionfs for more than a year now (to keep my local source 
tree changes separate from the "official" tree) and have had no problems 
other than an occassional (once a month or so) panic.  Seems that when 
the daily cron task kicks off, I sometimes get a panic about "cleaned 
vnode isn't".  Never seems to cause any file system corruption, though.

I've also made some changes recently to permit the unionfs code to 
actually work in its lkm form.  These changes have just yesterday been 
submitted as a pr, so I have no idea when (or if) they'll make it into 
the official sources.