[PATCH v7 3/9] arm64, kfence: enable KFENCE for ARM64

[Jann Horn]

On Tue, Nov 3, 2020 at 6:59 PM Marco Elver <elver at google.com> wrote:
> Add architecture specific implementation details for KFENCE and enable
> KFENCE for the arm64 architecture. In particular, this implements the
> required interface in <asm/kfence.h>.
>
> KFENCE requires that attributes for pages from its memory pool can
> individually be set. Therefore, force the entire linear map to be mapped
> at page granularity. Doing so may result in extra memory allocated for
> page tables in case rodata=full is not set; however, currently
> CONFIG_RODATA_FULL_DEFAULT_ENABLED=y is the default, and the common case
> is therefore not affected by this change.
>
> Reviewed-by: Dmitry Vyukov <dvyukov at google.com>
> Co-developed-by: Alexander Potapenko <glider at google.com>
> Signed-off-by: Alexander Potapenko <glider at google.com>
> Signed-off-by: Marco Elver <elver at google.com>

Reviewed-by: Jann Horn <jannh at google.com>