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Subject: Re: visible memory seems wrong in kexec crash dump kernel
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Chris Friesen <cbf123@mail.usask.ca>
Date: Mon, 15 Jul 2013 09:11:27 +1000
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On Sun, 2013-07-14 at 17:08 -0600, Chris Friesen wrote:
> > So for memory starting at 0 it should be memory@0
> 
> There are a fair number of dts files in the kernel tree that don't 
> specify an address for the memory node.
> 
> If the kernel accepts it without an address, it seems logical that kexec 
> should as well.

As long as kexec doesn't start being stupid when there are several nodes
and doesn't pick up the "first one in device-tree order" instead of the
one at 0...

I've been hit by that sort of bugs before (though not specifically in
kexec).

> Or maybe the kernel should just implicitly assume an address of zero and 
> export it as such in /proc/device-tree?

I don't want /proc/device-tree to expose something different than what's in
the actual device-tree, that would be the source for endless horrors.

We already are borderline with the occasional renaming we do in the case of
duplicate name+property...

Cheers,
Ben.