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Date: Thu, 3 Aug 2017 16:51:55 +0800
From: Chao Fan <fanc.fnst@cn.fujitsu.com>
To: <linux-kernel@vger.kernel.org>, <x86@kernel.org>
CC: <hpa@zytor.com>, <tglx@linutronix.de>, <mingo@redhat.com>,
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        <izumi.taku@jp.fujitsu.com>
Subject: [POC] Get acpi table to limit memory scope chosen by KASLR to home
 SB when "movable_node" is specified
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Hi all,

Here is an issue about movable_node and KASLR.
Currently, KASLR works well with "mem=", by which we can limit the scope of
memory chosen by KASLR. But if we use "movable_node" independently without
"mem=", we don't know the scope of memory in the home SB, which will cause
the memory of hotplug SB may be chosen by KASLR.
To solve this problem, I want to do this job:
If "movable_node" is specified, try to get the acpi table and find the scope
of memory in home SB, then set "mem_limit".

The order of getting table is:
boot_params
    \-systab
        \-efi tables
             \-rsdp
                 \-rsdt or xsdt
                      \-acpi root table list
                            \-acpi srat mem affinity

I am not sure if it's OK for community.
If there are any problems, please let me know.
Any comments will be welcome.

Thanks,
Chao Fan