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Subject: Re: [PATCH 2/2] Register bootmem pages at boot on powerpc
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Date: Tue, 13 Aug 2013 07:13:05 +1000
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On Mon, 2013-08-12 at 08:01 -0500, Nathan Fontenot wrote:
> > Can you tell me a bit more, the above makes me nervous...
> 
> Ok, I agree. that message isn't quite right.
> 
> What I wanted to convey is that memory hotplug is not fully supported
> on powerpc with SPARSE_VMEMMAP enabled.. Perhaps the message should read
> "Memory hotplug is not fully supported for bootmem info nodes".
> 
> Thoughts?

Since SPARSE_VMEMMAP is our default and enabled in our distros, that mean
that memory hotplug isn't fully supported for us in general ?

What do you mean by "not fully supported" ? What precisely is missing ?
What will happen if one tries to plug or unplug memory?

Shouldn't we fix it ?

Cheers,
Ben.