Re: [RFC PATCH 0/4] x86/boot/KASLR: Parse ACPI table and limit kaslr in immovable memory.

From: Baoquan He
Date: Mon Jul 02 2018 - 08:19:05 EST


Hi Chao,

On 06/12/18 at 04:10pm, Chao Fan wrote:
> *** Issues need be discussed
> There are several issues I am not quite sure, please help review and
> give suggestions:
>
> 1) In PATCH 1, I copy the structures and functions from ACPI head file,
> so that ACPI head file will never been used here. I am not sure
> whether it's good to include ACPI head file or use the method in
> PATCH 1. If people think we can use ACPI head files directely, I
> will remove the PATCH 1.

Usaully we try to reuse code even though they are located in different
life space. I think it applies to this SRAT handling. Copying ACPI codes
to kernel decompressing looks messy. Is there better way to reuse ACPI
code and read SRAT table, then get what we need in a simple way?

Thanks
Baoquan
>
> ***Test results:
> - I did a very simple test, and it can get the memory information in
> bios and efi KVM guest machine, and put it by early printk. But no
> more tests, so it's with RFC tag.
>
> Any comments will be welcome.
>
>
> Chao Fan (4):
> x86/boot: Add acpitb.h to help parse acpi tables
> x86/boot: Add acpitb.c to parse acpi tables
> x86/boot/KASLR: Walk srat tables to filter immovable memory
> x86/boot/KASLR: Limit kaslr to choosing the immovable memory
>
> arch/x86/boot/compressed/Makefile | 1 +
> arch/x86/boot/compressed/acpitb.c | 245 ++++++++++++++++++++++++++++++
> arch/x86/boot/compressed/acpitb.h | 175 +++++++++++++++++++++
> arch/x86/boot/compressed/kaslr.c | 120 +++++++++++++--
> 4 files changed, 530 insertions(+), 11 deletions(-)
> create mode 100644 arch/x86/boot/compressed/acpitb.c
> create mode 100644 arch/x86/boot/compressed/acpitb.h
>
> --
> 2.17.0
>
>
>