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Date:   Thu, 10 Dec 2020 23:16:28 +1100
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     Ben Greear <greearb@candelatech.com>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        Steve deRosier <derosier@cal-sierra.com>
Subject: Re: [PATCH v2] crypto: aesni - add ccm(aes) algorithm implementation
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On Thu, Dec 10, 2020 at 01:03:56PM +0100, Ard Biesheuvel wrote:
>
> But we should probably start policing this a bit more. For instance, we now have
> 
> drivers/net/macsec.c:
> 
> /* Pick a sync gcm(aes) cipher to ensure order is preserved. */
> tfm = crypto_alloc_aead("gcm(aes)", 0, CRYPTO_ALG_ASYNC);
> 
> (btw the comment is bogus, right?)
> 
> TLS_SW does the same thing in net/tls/tls_device_fallback.c.

Short of us volunteering to write code for every user out there
I don't see a way out.
 
> Async is obviously needed for h/w accelerators, but could we perhaps
> do better for s/w SIMD algorithms? Those are by far the most widely
> used ones.

If you can come up with a way that avoids the cryptd model without
using a fallback obviously that would be the ultimate solution.

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