[PATCH v3 0/2] arm64/acpi: restrict AML opregion memory access

[Ard Biesheuvel]

(+ James)

On Fri, 26 Jun 2020 at 18:58, Ard Biesheuvel <ardb at kernel.org> wrote:
>
> v2:
> - do a more elaborate check on the region, against the EFI memory map
>
> v3:
> - split into two patches
> - fallback to __ioremap() for ACPI reclaim memory, in case it is not covered
>   by the linear mapping (e.g., when booting a kdump kernel)
>
> Ard Biesheuvel (2):
>   arm64/acpi: disallow AML memory opregions to access kernel memory
>   arm64/acpi: disallow writeable AML opregion mapping for EFI code
>     regions
>

With some adult supervision from James (thanks!), I have given this a
spin myself with kexec under QEMU/kvm, to boot a crashkernel, and
everything works as expected.


>  arch/arm64/include/asm/acpi.h | 15 +---
>  arch/arm64/kernel/acpi.c      | 75 ++++++++++++++++++++
>  2 files changed, 76 insertions(+), 14 deletions(-)
>
> --
> 2.27.0
>