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Date: Sat, 30 Jun 2018 22:53:36 +0300
From: Konstantin Belousov <kostikbel@gmail.com>
To: Rick Macklem <rmacklem@uoguelph.ca>
Cc: "freebsd-current@freebsd.org" <freebsd-current@freebsd.org>
Subject: Re: change of nfsd->kernel interface in head
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On Sat, Jun 30, 2018 at 06:39:57PM +0000, Rick Macklem wrote:
> r335012 (the big patch that added the pNFS server support) revised the nfsd->kernel
> nfssvc(2) syscall interface.
> It has compatibility code, so that old nfsd binaries still work.
> 
> I now need to revise this interface again to add a new pNFS server feature.
> Since the revised interface is only in head/current starting at r335012, I
> believe I can revise it again without an additional compatibility shim for
> r335012 or later nfsd binaries. Is this correct?
> 
> I would post a HEADS UP to this email list and the only code affected would be
> sites running current/head and using the "-p" (pNFS server) option, so they would
> be few, if any.
> 

You are right.

More, it is not clear if nfsd interface should be considered part of the
stable contract even on stable.  It is clearly the management interface,
nfsd is not required to get the system operational enough to install the
right nfsd.  If possible, stable should not add more troubles for upgrade,
while for HEAD it does not matter.