From: Nick Desaulniers <ndesaulniers@google.com>
To: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Nathan Chancellor <natechancellor@gmail.com>,
Herbert Xu <herbert@gondor.apana.org.au>,
linux-crypto@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] crypto: ccree - avoid implicit enum conversion
Date: Thu, 11 Oct 2018 13:50:31 -0700 [thread overview]
Message-ID: <CAKwvOdkUnpxJe+zXMWDHsfozi9D-TpPZgmasciRU-nkCA9xOGg@mail.gmail.com> (raw)
In-Reply-To: <CAOtvUMezOMmyE=FW+nRqrR+r2NsNOCCXWwp0fja9gF7j-xQAnw@mail.gmail.com>
On Thu, Oct 11, 2018 at 12:47 AM Gilad Ben-Yossef <gilad@benyossef.com> wrote:
>
> Hi Nick,
>
> On Thu, Oct 11, 2018 at 2:49 AM Nick Desaulniers
> <ndesaulniers@google.com> wrote:
> >
> > $ grep -r set_cipher_config0 -n
> >
> > shows a healthy mix of DESC_DIRECTION_ENCRYPT_ENCRYPT,
> > HASH_DIGEST_RESULT_LITTLE_ENDIAN, and DRV_CRYPTO_DIRECTION_ENCRYPT
> > (all enumeration values of different enums).
> >
> > >
> > > drivers/crypto/ccree/cc_aead.c:1643:30: warning: implicit conversion
> > > from enumeration type 'enum drv_hash_hw_mode' to different enumeration
> > > type 'enum drv_cipher_mode' [-Wenum-conversion]
> > > set_cipher_mode(&desc[idx], DRV_HASH_HW_GHASH);
> >
> > Looks like a lot fewer call sites using DRV_HASH_HW_GHASH; same value
> > as DRV_CIPHER_OFB (different enum), but can a block cipher mode and a
> > hash be valid values for pdesc->word[4]?
> >
> > >
> > > Since this fundamentally isn't a problem because these values just
> > > represent simple integers for a shift operation, make it clear to Clang
> > > that this is okay by making the mode parameter in both functions an int.
> >
> > This also looks like the simplest fix to me, assuming the values of
> > all of these enums are valid for whatever pdesc->word[4] is. Can the
> > maintainers explain what is CC7x-DESC what the comment makes reference
> > to?
>
> They indeed are. CC7x-DESC is a shorthand for "CryptoCell 7xx
> Descriptor" used in the hardware documents.
> These descriptors are comprised of fields with context sensitive
> meaning, hence this "overloading".
>
> Given this overloading of meaning an "int" type is indeed a better
> suited type here.
Sounds like they're valid values then. Thanks for the info.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
>
> Thanks,
> Gilad
> --
> Gilad Ben-Yossef
> Chief Coffee Drinker
>
> values of β will give rise to dom!
--
Thanks,
~Nick Desaulniers
next prev parent reply other threads:[~2018-10-11 20:50 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-10 21:40 [PATCH] crypto: ccree - avoid implicit enum conversion Nathan Chancellor
2018-10-10 23:49 ` Nick Desaulniers
2018-10-11 7:47 ` Gilad Ben-Yossef
2018-10-11 20:50 ` Nick Desaulniers [this message]
2018-10-11 7:39 ` Gilad Ben-Yossef
2018-10-17 6:22 ` Herbert Xu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAKwvOdkUnpxJe+zXMWDHsfozi9D-TpPZgmasciRU-nkCA9xOGg@mail.gmail.com \
--to=ndesaulniers@google.com \
--cc=gilad@benyossef.com \
--cc=herbert@gondor.apana.org.au \
--cc=linux-crypto@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=natechancellor@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.