On Tue, Oct 05, 2021 at 04:57:55PM +0000, Tim.Bird@sony.com wrote:

quoted

-----Original Message-----
From: Greg KH <gregkh@linuxfoundation.org>
Sent: Tuesday, October 5, 2021 8:17 AM
To: Luis Chamberlain <mcgrof@kernel.org>
Cc: tj@kernel.org; akpm@linux-foundation.org; minchan@kernel.org; jeyu@kernel.org; shuah@kernel.org; bvanassche@acm.org;
dan.j.williams@intel.com; joe@perches.com; tglx@linutronix.de; keescook@chromium.org; rostedt@goodmis.org; linux-
spdx@vger.kernel.org; linux-doc@vger.kernel.org; linux-block@vger.kernel.org; linux-fsdevel@vger.kernel.org; linux-
kselftest@vger.kernel.org; linux-kernel@vger.kernel.org
Subject: Re: [PATCH v8 03/12] selftests: add tests_sysfs module

On Mon, Sep 27, 2021 at 09:37:56AM -0700, Luis Chamberlain wrote:

quoted

--- /dev/null
+++ b/lib/test_sysfs.c

@@ -0,0 +1,921 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR copyleft-next-0.3.1
+/*
+ * sysfs test driver
+ *
+ * Copyright (C) 2021 Luis Chamberlain <mcgrof@kernel.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or at your option any
+ * later version; or, when distributed separately from the Linux kernel or
+ * when incorporated into other software packages, subject to the following
+ * license:

This is a very strange license grant, which I'm not sure is covered by any
current SPDX syntax.
" when distributed separately from the Linux kernel or when incorporated into
other software packages, subject to the following license:"

drivers/xen/events/events_fifo.c has that same language.

Why would we care about the license used when the code is used in a non-kernel
project?  If it is desired for the code to be available outside the kernel under a
different license, then surely the easiest thing is to make it available separately
under that license.  I'm not sure why the kernel needs to carry this license for
non-kernel use of the code.

I would recommend giving this a GPLv2 SPDX header, and maybe in the comment
at the top of the file put a reference to a git repository where the code can be
obtained under a different license.

Keeping the dual let's new updates directly on the kernel benefit from
evolution. A fork would stagnate it in place and would require updates
separately.

  Luis