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Date: Tue, 24 Sep 2013 10:05:45 -0400
From: Tejun Heo <tj@kernel.org>
To: Zhang Yanfei <zhangyanfei.yes@gmail.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>,
        "Rafael J . Wysocki" <rjw@sisk.pl>, lenb@kernel.org,
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Subject: Re: [PATCH 4/6] x86/mem-hotplug: Support initialize page tables
 bottom up
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On Tue, Sep 24, 2013 at 09:53:47PM +0800, Zhang Yanfei wrote:
> OK, this is just because we allocate pagtables just above the kernel.
> And if we use up the BRK space that is reserved for inital pagetables,
> we will use memblock to allocate memory for pagetables, and the memory
> allocated here should be mapped already. So we first map [kernel_end, end)
> to make memory above the kernel be mapped as soon as possible. And then
> use pagetables allocated above the kernel to map [ISA_END_ADDRESS, kernel_end).

I see.  The code seems fine to me then.  Can you please add comment
explaining why the split calls are necessary?

Thanks.

-- 
tejun
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