From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH 20/31] lmb: Add __NOT_KEEP_LMB to put lmb code to .init
Date: Tue, 30 Mar 2010 08:44:57 +1100
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To: David Miller <davem@davemloft.net>
Cc: yinghai@kernel.org, michael@ellerman.id.au, mingo@elte.hu, tglx@linutronix.de, hpa@zytor.com, akpm@linux-foundation.org, torvalds@linux-foundation.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org

On Mon, 2010-03-29 at 12:11 -0700, David Miller wrote:
> From: Yinghai Lu <yinghai@kernel.org>
> Date: Mon, 29 Mar 2010 11:39:52 -0700
> 
> > On 03/29/2010 11:34 AM, David Miller wrote:
> >> From: Yinghai Lu <yinghai@kernel.org>
> >> Date: Mon, 29 Mar 2010 09:20:28 -0700
> >> 
> >>> BTW, it seems only PowerPC need to keep lmb after init stage, right ?
> >> 
> >> For now.  Sparc64 will need it at some point in the future.
> > 
> > for memory hotplug support?
> 
> Yes.

We also can use it to implement page_is_ram() which might help
get /dev/mem cachability setting right by default one day :-)

However, we only need to keep the memory list, not the reserve list.

Cheers,
Ben.