Date: Tue, 16 Jan 2018 16:30:32 +0100
From: Boris Brezillon <boris.brezillon@free-electrons.com>
To: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>,
        =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= <rafal@milecki.pl>,
        Brian Norris <computersforpeace@gmail.com>,
        David Woodhouse <dwmw2@infradead.org>,
        Marek Vasut <marek.vasut@gmail.com>,
        Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>,
        linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [REGRESSION] linux-next panics when trying to mount root
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On Tue, 16 Jan 2018 16:02:35 +0100
Peter Rosin <peda@axentia.se> wrote:

> On 2018-01-16 15:21, Boris Brezillon wrote:
> > On Tue, 16 Jan 2018 14:56:52 +0100
> > Peter Rosin <peda@axentia.se> wrote:
> >   
> >> Hmmm, I guess the question is if the command line should override the
> >> device tree or not?  
> > 
> > Yep, that's the problem. Now the core parses the compatible to decides
> > which part parser should be used. The thing is, the "cmdline" parser is
> > not yet exposing a compatible id, and even if it was, this would
> > require patching all DTs to add this new compatible.
> > 
> > 	partitions {
> > 		compatible = "cmdline", "fixed-partitions";
> > 		...
> > 	};
> > 
> > Not really an option, so I'll drop the 2 patches for now until we find a
> > better solution.
> >   
> >> I'm going to send a patch for the above dts change either way...  
> > 
> > If you want, but that does not solve the problem: we should not break
> > existing users.  
> 
> Well, don't let these devices stop you, they will not get a new kernel
> w/o also getting a new dtb, and I can handle this just fine. But maybe
> I'm just the first reporter and you'd rather not risk anything? Anyway,
> just wanted to let you know where I stand...

Unfortunately, at91 is not the only platform to have "fixed-partitions"
defined in its DTs, and I guess users of other platforms also like to
override the default MTD layout by their own using mtdparts.I'd like to
find a solution that keeps everyone happy.