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Date:   Fri, 19 Jul 2019 00:22:09 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc:     Pascal Van Leeuwen <pvanleeuwen@verimatrix.com>,
        Milan Broz <gmazyland@gmail.com>,
        Horia Geanta <horia.geanta@nxp.com>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
        "dm-devel@redhat.com" <dm-devel@redhat.com>
Subject: Re: xts fuzz testing and lack of ciphertext stealing support
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On Thu, Jul 18, 2019 at 06:19:24PM +0200, Ard Biesheuvel wrote:
>
> Note that for software algorithms such as the bit sliced NEON
> implementation of AES, which can only operate on 8 AES blocks at a
> time, doing the final 2 blocks sequentially is going to seriously
> impact performance. This means whatever wrapper we invent around xex()
> (or whatever we call it) should go out of its way to ensure that the
> common, non-CTS case does not regress in performance, and the special
> handling is only invoked when necessary (which will be never).

Agreed.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt