Re: [PATCH v8 0/3] x86/boot/KASLR: Parse ACPI table and limit kaslr in immovable memory

Chao Fan
2018-10-10T09:12:05Z

On Wed, Oct 10, 2018 at 05:06:20PM +0800, Baoquan He wrote:
>Hi Boris,
>
>On 10/10/18 at 10:59am, Borislav Petkov wrote:
>> ... and we just picked up
>>
>> https://lkml.kernel.org/r/20181001140843.26137-1-msys.mizuma@gmail.com
>>
>> and without having looked at the rest of your stuff, if people accept
>> your solution, we don't need the silly parameter anymore, right?
>>
>> Which means, we should not rush the whole thing yet until the whole
>> KASLR vs movable memory gets solved properly.
>
>Masa's patches solves the problem in memory region KASLR which later hot
>added memory may be big than the default padding 10 TB.
>
>Chao's patches is trying to fix a conflict between 'movable_node' and
>kernel text KASLR. If 'movable_node' specified, we rely on SRAT to get
>which memory region is movable or immovable, and movable region can be
>hot removed. But if kernel is randomized into movable memory, it can't
>be hot removed any more, this is a regression after KASLR introduced.
>So this is a different issue than Masa's.

Yes, they are two issues.
But if we can get more memory information by the function in
the new file acpi.c, semms it's helfpul to Masa's issue.

Thanks,
Chao Fan

>
>Thanks
>Baoquan
>
>