Subject: Re: [PATCH net-next v3 07/11] uapi: wireguard: generate header with ynl-gen

From: "Jason A. Donenfeld" <[email-masked]>
Date: Thu, 20 Nov 2025 01:55:46 +0100

On Tue, Nov 18, 2025 at 04:53:15PM -0800, Jakub Kicinski wrote:
> On Tue, 18 Nov 2025 16:17:21 +0100 Jason A. Donenfeld wrote:
> > On Wed, Nov 05, 2025 at 06:32:16PM +0000, Asbjørn Sloth Tønnesen wrote:
> > > Use ynl-gen to generate the UAPI header for wireguard.
> > > diff --git a/include/uapi/linux/wireguard.h b/include/uapi/linux/wireguard.h
> > > index a2815f4f2910..dc3924d0c552 100644
> > > --- a/include/uapi/linux/wireguard.h
> > > +++ b/include/uapi/linux/wireguard.h
> > > @@ -1,32 +1,28 @@
> > > -/* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR MIT */
> > > -/*
> > > - * Copyright (C) 2015-2019 Jason A. Donenfeld <[email-masked]>. All Rights Reserved.
> > > - */
> > > +/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */
> > > +/* Do not edit directly, auto-generated from: */
> > > +/*	Documentation/netlink/specs/wireguard.yaml */
> > > +/* YNL-GEN uapi header */  
> > 
> > Same desire here -- can this get auto generated at compile time (or in
> > headers_install time).
> 
> IMHO generating uAPI on the fly has more downsides than benefits.
> For one thing people grepping the code and looking and lxr will
> never find the definition. All the user space code in tools/ is
> generated at build time, but the amount of kernel code we generate
> is not significant at this stage. Not significant enough to complicate
> everyone's life..

I was thinking that doing this automatically at compile-time or
install-time would be _less_ complicated, not more, since everything
would be kept in sync automatically and such. But alright, so be it.