Date: Thu, 14 Dec 2017 19:50:03 -0200
From: Mauro Carvalho Chehab <mchehab@kernel.org>
To: Greg KH <gregkh@linuxfoundation.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Joe Perches <joe@perches.com>, Dhaval Shah <dhaval23031987@gmail.com>,
        hyun.kwon@xilinx.com, michal.simek@xilinx.com,
        linux-media@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] media: v4l: xilinx: Use SPDX-License-Identifier
Message-ID: <20171214194536.2269667d@recife.lan>
In-Reply-To: <20171214205706.GA1856@kroah.com>
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        <2967655.MWOA0IsQOS@avalon>
        <20171214200851.GA27849@kroah.com>
        <3484237.SQf3uXUed3@avalon>
        <20171214205706.GA1856@kroah.com>
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Em Thu, 14 Dec 2017 21:57:06 +0100
Greg KH <gregkh@linuxfoundation.org> escreveu:

> On Thu, Dec 14, 2017 at 10:44:16PM +0200, Laurent Pinchart wrote:
> > Hi Greg,
> > 
> > On Thursday, 14 December 2017 22:08:51 EET Greg KH wrote:  
> > > On Thu, Dec 14, 2017 at 09:05:27PM +0200, Laurent Pinchart wrote:  
> > > > On Thursday, 14 December 2017 20:54:39 EET Joe Perches wrote:  
> > > >> On Thu, 2017-12-14 at 20:37 +0200, Laurent Pinchart wrote:  
> > > >>> On Thursday, 14 December 2017 20:32:20 EET Joe Perches wrote:  
> > > >>>> On Thu, 2017-12-14 at 20:28 +0200, Laurent Pinchart wrote:  
> > > >>>>> On Thursday, 14 December 2017 19:05:27 EET Mauro Carvalho Chehab   
> > wrote:  
> > > >>>>>> Em Fri,  8 Dec 2017 18:05:37 +0530 Dhaval Shah escreveu:  
> > > >>>>>>> SPDX-License-Identifier is used for the Xilinx Video IP and
> > > >>>>>>> related drivers.
> > > >>>>>>> 
> > > >>>>>>> Signed-off-by: Dhaval Shah <dhaval23031987@gmail.com>  
> > > >>>>>> 
> > > >>>>>> Hi Dhaval,
> > > >>>>>> 
> > > >>>>>> You're not listed as one of the Xilinx driver maintainers. I'm
> > > >>>>>> afraid that, without their explicit acks, sent to the ML, I can't
> > > >>>>>> accept a patch touching at the driver's license tags.  
> > > >>>>> 
> > > >>>>> The patch doesn't change the license, I don't see why it would cause
> > > >>>>> any issue. Greg isn't listed as the maintainer or copyright holder
> > > >>>>> of any of the 10k+ files to which he added an SPDX license header in
> > > >>>>> the last kernel release.  
> > > >>>> 
> > > >>>> Adding a comment line that describes an implicit or
> > > >>>> explicit license is different than removing the license
> > > >>>> text itself.  
> > > >>> 
> > > >>> The SPDX license header is meant to be equivalent to the license text.  
> > > >> 
> > > >> I understand that.
> > > >> At a minimum, removing BSD license text is undesirable
> > > >> 
> > > >> as that license states:
> > > >>  *    * Redistributions of source code must retain the above copyright
> > > >>  *      notice, this list of conditions and the following disclaimer.
> > > >> 
> > > >> etc...  
> > > > 
> > > > But this patch only removes the following text:
> > > > 
> > > > - * This program is free software; you can redistribute it and/or modify
> > > > - * it under the terms of the GNU General Public License version 2 as
> > > > - * published by the Free Software Foundation.
> > > > 
> > > > and replaces it by the corresponding SPDX header.
> > > >   
> > > >>> The only reason why the large SPDX patch didn't touch the whole kernel
> > > >>> in one go was that it was easier to split in in multiple chunks.  
> > > >> 
> > > >> Not really, it was scripted.  
> > > > 
> > > > But still manually reviewed as far as I know.
> > > >   
> > > >>> This is no different than not including the full GPL license in every
> > > >>> header file but only pointing to it through its name and reference, as
> > > >>> every kernel source file does.  
> > > >> 
> > > >> Not every kernel source file had a license text
> > > >> or a reference to another license file.  
> > > > 
> > > > Correct, but the files touched by this patch do.
> > > > 
> > > > This issue is in no way specific to linux-media and should be decided upon
> > > > at the top level, not on a per-subsystem basis. Greg, could you comment
> > > > on this ?  
> > > 
> > > Comment on what exactly?  I don't understand the problem here, care to
> > > summarize it?  
> > 
> > In a nutshell (if I understand it correctly), Dhaval Shah submitted https://
> > patchwork.kernel.org/patch/10102451/ which replaces
> > 
> > +// SPDX-License-Identifier: GPL-2.0
> > [...]
> > - *
> > - * This program is free software; you can redistribute it and/or modify
> > - * it under the terms of the GNU General Public License version 2 as
> > - * published by the Free Software Foundation.
> > 
> > in all .c and .h files of the Xilinx V4L2 driver (drivers/media/platform/
> > xilinx). I have reviewed the patch and acked it. Mauro then rejected it, 
> > stating that he can't accept a change to license text without an explicit ack 
> > from the official driver's maintainers. My position is that such a change 
> > doesn't change the license and thus doesn't need to track all copyright 
> > holders, and can be merged without an explicit ack from the respective 
> > maintainers.  
> 
> Yes, I agree with you, no license is being changed here, and no
> copyright is either.
> 
> BUT, I know that most major companies are reviewing this process right
> now.  We have gotten approval from almost all of the major kernel
> developer companies to do this, which is great, and supports this work
> as being acceptable.
> 
> So it's nice to ask Xilinx if they object to this happening, which I
> guess Mauro is trying to say here (in not so many words...)  To at least
> give them the heads-up that this is what is going to be going on
> throughout the kernel tree soon, and if they object, it would be good to
> speak up as to why (and if they do, I can put their lawyers in contact
> with some lawyers to explain it all to them.)

Yes, that's basically what I'm saying. 

I don't feel comfortable on signing a patch changing the license text 
without giving the copyright owners an opportunity and enough time
to review it and approve, or otherwise comment about such changes.


Thanks,
Mauro