Re: [POC] Get acpi table to limit memory scope chosen by KASLR to home SB when "movable_node" is specified

From: Chao Fan
Date: Thu Aug 03 2017 - 05:04:24 EST

On Thu, Aug 03, 2017 at 04:59:26PM +0800, Dou Liyang wrote:
>Cc ACPI maintainers and mail list

So many thanks.

>At 08/03/2017 04:51 PM, Chao Fan wrote:
>> 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 good to do this job in this period,
so I want to get the feedback of community.

Chao Fan

>> 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