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Date: Mon, 21 Feb 2011 10:43:18 +0100
From: Tejun Heo <tj@kernel.org>
To: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@elte.hu>, "H. Peter Anvin" <hpa@zytor.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Cyrill Gorcunov <gorcunov@gmail.com>
Subject: Re: [PATCH 2/4] x86, numa: Do not adjust start/end for
 early_node_mem()
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Hello,

On Sat, Feb 19, 2011 at 08:17:11PM -0800, Yinghai Lu wrote:
> > The old code guarantees that the range is from a single zone, and even
> > though memblock may be top -> down, it seems like there would be
> > configurations where this would still be an issue (perhaps simulating it
> > with numa=fake for testing?) if it crosses the boundary.
> 
> memblock_x86_find_in_range_node() will go over with early_node_map[].
> so it will always can get right on node allocation.

I think always doing top-down allocation should be enough as long as
there's no highmem, which we don't have on 64bit.  That said, the
patch description should note the behavior difference.  Yinghai, care
to add a bit more detail to the patch description?

Thanks.

-- 
tejun