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From:   Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date:   Wed, 12 Sep 2018 20:19:21 +0200
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Subject: Re: [PATCH net-next v3 02/17] zinc: introduce minimal cryptography library
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     Eric Biggers <ebiggers@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Netdev <netdev@vger.kernel.org>,
        David Miller <davem@davemloft.net>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andrew Lutomirski <luto@kernel.org>,
        Samuel Neves <sneves@dei.uc.pt>,
        Jean-Philippe Aumasson <jeanphilippe.aumasson@gmail.com>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>
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On 12 September 2018 at 20:16, Jason A. Donenfeld <Jason@zx2c4.com> wrote:
> Hi Eric,
>
> On Wed, Sep 12, 2018 at 12:08 AM Eric Biggers <ebiggers@kernel.org> wrote:
>> I'd strongly prefer the assembly to be readable too.  Jason, I'm not sure if
>> you've actually read through the asm from the OpenSSL implementations, but the
>> generated .S files actually do lose a lot of semantic information that was in
>> the original .pl scripts.
>
> The thing to keep in mind is that the .S was not directly and blindly
> generated from the .pl. We started with the output of the .pl, and
> then, particularly in the case of x86_64, worked with it a lot, and
> now it's something a bit different. We've definitely spent a lot of
> time reading that assembly.
>

Can we please have those changes as a separate patch? Preferably to
the .pl file rather than the .S file, so we can easily distinguish the
code from upstream from the code that you modified.

> I'll see if I can improve the readability with some register name
> remapping on ARM. No guarantees, but I'll play a bit and see if I can
> make it a bit better.
>
> Jason