unionfs bugs, a partial patch and some comments [Was: Re: 1-BETA3 Panic: __lockmgr_args: downgrade a recursed lockmgr nfs @ /usr/local/share/deploy-tools/RELENG_11/src/sys/fs/unionfs/union_vnops.c:1905]

[Konstantin Belousov]

On Thu, Mar 09, 2017 at 10:49:01PM +0000, Rick Macklem wrote:
> Konstantin Belousov wrote:
> > I did not touched unionfs, and have no plans to.  It is equally broken in
> > all relevant versions of FreeBSD.
> Heh, heh. I chuckled when I read this. I think he's trying to say
> "it probably won't ever be fixed". My understanding is that it would
> require a major redesign of the FreeBSD VFS to make it fully stackable
> to fix unionfs and that isn't happening anytime soon...
>

I mean that there is nobody who is both interested in unionfs and capable
of fixing it, and it was so at least from the 8.x times.

Also, I do not think that VFS needs a redesign to support unionfs-like
operations.  The problems that current unionfs has are its local problems.