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From:   Ard Biesheuvel <ardb@kernel.org>
Date:   Thu, 10 Dec 2020 13:19:18 +0100
Message-ID: <CAMj1kXE-+35tfO87024xB274ZVOu7HTHqDa8o-hjoxDasd8p7g@mail.gmail.com>
Subject: Re: [PATCH v2] crypto: aesni - add ccm(aes) algorithm implementation
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     Ben Greear <greearb@candelatech.com>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        Steve deRosier <derosier@cal-sierra.com>
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On Thu, 10 Dec 2020 at 13:16, Herbert Xu <herbert@gondor.apana.org.au> wrote:
>
> 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.
>

Could we disable softirq handling in these regions?