Date: Mon, 24 Oct 2016 13:20:00 -0500
From: Reza Arbab <arbab@linux.vnet.ibm.com>
To: Michael Ellerman <mpe@ellerman.id.au>,
        Alistair Popple <apopple@au1.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>, Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Stewart Smith <stewart@linux.vnet.ibm.com>, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, Tang Chen <tangchen@cn.fujitsu.com>,
        linux-mm@kvack.org,
        "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>,
        Bharata B Rao <bharata@linux.vnet.ibm.com>,
        Nathan Fontenot <nfont@linux.vnet.ibm.com>
Subject: Re: [PATCH v4 2/5] drivers/of: do not add memory for unavailable
 nodes
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On Mon, Oct 24, 2016 at 09:24:04PM +1100, Michael Ellerman wrote:
>The code already looks for "linux,usable-memory" in preference to 
>"reg". Can you use that instead?

Yes, we could set the size of "linux,usable-memory" to zero instead of 
setting status to "disabled".

I'll send a v5 of this set which drops 1/5 and 2/5. That would be the 
only difference here.

>That would have the advantage that existing kernels already understand
>it.
>
>Another problem with using "status" is we could have device trees out
>there that have status = disabled and we don't know about it, and by
>changing the kernel to use that property we break people's systems.
>Though for memory nodes my guess is that's not true, but you never know ...

-- 
Reza Arbab