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From:   Marco Elver <elver@google.com>
Date:   Wed, 9 Sep 2020 17:13:45 +0200
Message-ID: <CANpmjNMRMkFxdGHuyyWEPhMiW-uF4qjiKKRRrd_s13X2P6cv9Q@mail.gmail.com>
Subject: Re: [PATCH RFC 03/10] arm64, kfence: enable KFENCE for ARM64
To:     Catalin Marinas <catalin.marinas@arm.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Will Deacon <will@kernel.org>,
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Hello arm64 maintainers,

On Mon, 7 Sep 2020 at 15:41, Marco Elver <elver@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>. Currently, the arm64 version does
> not yet use a statically allocated memory pool, at the cost of a pointer
> load for each is_kfence_address().

> For ARM64, we would like to solicit feedback on what the best option is
> to obtain a constant address for __kfence_pool. One option is to declare
> a memory range in the memory layout to be dedicated to KFENCE (like is
> done for KASAN), however, it is unclear if this is the best available
> option. We would like to avoid touching the memory layout.

We can't yet tell what the best option for this might be. So, any
suggestions on how to go about switching to a static pool would be
much appreciated.

Many thanks,
-- Marco