Re: [PATCH v3] powerpc: Add missing SPDX license identifiers

> On Fri, Jan 21, 2022 at 03:13:50PM +0000, Christophe Leroy wrote:
> > Isn't it what GPL-2.0+ means ?

Greg Kroah-Hartman wrote:
> Yes, but look further down, as I point out below...
>
> > >> 	include/asm/epapr_hcalls.h:/* SPDX-License-Identifier: GPL-2.0+ OR BSD */
> > >> 	include/asm/fsl_hcalls.h:/* SPDX-License-Identifier: GPL-2.0+ OR BSD */
> > >> 	include/asm/ibmebus.h:/* SPDX-License-Identifier: GPL-2.0 OR OpenIB BSD */
> > >> 	include/asm/sfp-machine.h:/* SPDX-License-Identifier: LGPL-2.0+ */
> > >> 	kvm/mpic.c:// SPDX-License-Identifier: GPL-2.0
> > >> 	lib/crtsavres.S:/* SPDX-License-Identifier: GPL-2.0+ */
> > >> 	mm/book3s64/hash_4k.c:// SPDX-License-Identifier: LGPL-2.0
> > >> 	mm/book3s64/hash_64k.c:// SPDX-License-Identifier: LGPL-2.0
> > >> 	mm/book3s64/hash_hugepage.c:// SPDX-License-Identifier: LGPL-2.1
> > >> 	platforms/pseries/ibmebus.c:// SPDX-License-Identifier: GPL-2.0 OR OpenIB BSD
> > >> 	tools/head_check.sh:# SPDX-License-Identifier: GPL-2.0+
> > >> 	xmon/ppc.h:/* SPDX-License-Identifier: GPL-1.0+ */

If you're combining GPLv2-or-later works with LGPLv2.0/2.1 works, you'll have
to normalize to some GPLv2-based license (such as GPLv2-or-later), since
LGPLv2.1 requires that for combinations.  You won't be able to carry along
the "OR 3-Clause-BSD" part once the combination is made.  Similarly true with
GPLv2-or-later, but LGPL is the interesting one because it's explicit about
the need to change license notices to GPL notices when you combine.

 -- bkuhn