Re: [PATCH v4 1/3] xen/arm: Add imx8q{m,x} platform glue

[Julien Grall <julien@xxxxxxx>]

Hi John,

On 15/04/2024 12:17, John Ernberg wrote:
> Hi Julien,
>
> On 4/15/24 1:03 PM, Julien Grall wrote:
> > On 15/04/2024 11:50, Andrew Cooper wrote:
> > > On 15/04/2024 11:25 am, Julien Grall wrote:
> > > > Hi John,
> > > >
> > > > I saw this patch was committed. I have one question this may require
> > > > some adjustment.
> > > >
> > > > On 08/04/2024 17:11, John Ernberg wrote:
> > > > > ---
> > > > >     xen/arch/arm/platforms/Makefile |   1 +
> > > > >     xen/arch/arm/platforms/imx8qm.c | 139
> > > > > ++++++++++++++++++++++++++++++++
> > > > >     2 files changed, 140 insertions(+)
> > > > >     create mode 100644 xen/arch/arm/platforms/imx8qm.c
> > > > >
> > > > > diff --git a/xen/arch/arm/platforms/Makefile
> > > > > b/xen/arch/arm/platforms/Makefile
> > > > > index 8632f4115f..bec6e55d1f 100644
> > > > > --- a/xen/arch/arm/platforms/Makefile
> > > > > +++ b/xen/arch/arm/platforms/Makefile
> > > > > @@ -9,5 +9,6 @@ obj-$(CONFIG_ALL_PLAT)   += sunxi.o
> > > > >     obj-$(CONFIG_ALL64_PLAT) += thunderx.o
> > > > >     obj-$(CONFIG_ALL64_PLAT) += xgene-storm.o
> > > > >     obj-$(CONFIG_ALL64_PLAT) += brcm-raspberry-pi.o
> > > > > +obj-$(CONFIG_ALL64_PLAT) += imx8qm.o
> > > > >     obj-$(CONFIG_MPSOC_PLATFORM)  += xilinx-zynqmp.o
> > > > >     obj-$(CONFIG_MPSOC_PLATFORM)  += xilinx-zynqmp-eemi.o
> > > > > diff --git a/xen/arch/arm/platforms/imx8qm.c
> > > > > b/xen/arch/arm/platforms/imx8qm.c
> > > > > new file mode 100644
> > > > > index 0000000000..3600a073e8
> > > > > --- /dev/null
> > > > > +++ b/xen/arch/arm/platforms/imx8qm.c
> > > > > @@ -0,0 +1,139 @@
> > > > > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > > > The majority of Xen code is using GPL-2.0-only. In the early days for
> > > > Xen on Arm we started to use GPLv2+ which I consider it was a mistake.
> > > > Unfortunately this started to spread as people copied/pasted the same
> > > > copyright headers.
> > > >
> > > > So can you confirm whether you intended to use GPL-2.0+? If not would
> > > > you be able to send a patch to adjust it? (Better to it before there
> > > > are more modifications).
> > > Julien: I've called you out multiple times before.
> > And there are multiple thread explaining why I am requesting if we can
> > use GPLv2-only. In fact from CONTRIBUTING:
> >
> > The recommended license of a directory will depend on the COPYING file.
> > If the new file is using a different license, this should be highlighted
> > and discussed in the commit message or cover letter introducing the
> > file.
> Since part of the code was not written by me, but by Peng, I think both
> of us need to agree to a license change if one is to be made.
Ah I didn't realize that Peng also contributed. Let's wait if he is 
happy with the change.
Also, offline, I was pointed out that I could explain a little bit more 
why I asked if this could be changed. From [1]:
"IIRC from past discussion there are two broads concern with GPLv2+:
   - We are leaving the choice of which license applies to the person
copying the code. So if a new version is released that is less favorable
to the initial contributor, then we have no leverage.
   - Some companies are rather cautious to contribute code that may be
licensed under GPLv3 (would be allowed with GPLv2+).

The later is particularly a problem because not many people realize that
a fair part of Xen on Arm is GPLv2+. I never really understood why we
chose that (this was before my time) but this got spread as the existing
copyright was added to a new file. Admittely, the contributor should be
more cautious. But I would not say this is trivial to spot the difference."

Cheers,

[1] 
https://lore.kernel.org/xen-devel/f235f6f8-d585-4e24-7fc8-3f2df9240c9d@xxxxxxx/
--
Julien Grall