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Date:   Fri, 11 Sep 2020 19:15:59 +0100
From:   Will Deacon <will@kernel.org>
To:     Boyan Karatotev <boyan.karatotev@arm.com>
Cc:     linux-arm-kernel@lists.infradead.org,
        linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org,
        vincenzo.frascino@arm.com, amit.kachhap@arm.com,
        boian4o1@gmail.com, Shuah Khan <shuah@kernel.org>,
        Catalin Marinas <catalin.marinas@arm.com>
Subject: Re: [PATCH v2 0/4] kselftests/arm64: add PAuth tests
Message-ID: <20200911181558.GA21319@willie-the-truck>
References: <20200831110450.30188-1-boyan.karatotev@arm.com>
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On Mon, Aug 31, 2020 at 12:04:46PM +0100, Boyan Karatotev wrote:
> Pointer Authentication (PAuth) is a security feature introduced in ARMv8.3.
> It introduces instructions to sign addresses and later check for potential
> corruption using a second modifier value and one of a set of keys. The
> signature, in the form of the Pointer Authentication Code (PAC), is stored
> in some of the top unused bits of the virtual address (e.g. [54: 49] if
> TBID0 is enabled and TnSZ is set to use a 48 bit VA space). A set of
> controls are present to enable/disable groups of instructions (which use
> certain keys) for compatibility with libraries that do not utilize the
> feature. PAuth is used to verify the integrity of return addresses on the
> stack with less memory than the stack canary.

Any chance of a v3 addressing the couple of small comments from Dave on
the third patch, please? Then I can pick up the whole lot for 5.10.

Cheers,

Will