Date:   Thu, 9 Dec 2021 20:38:57 +0100
From:   Pavel Machek <pavel@ucw.cz>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     David Brazdil <dbrazdil@google.com>,
        Rob Herring <robh+dt@kernel.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Derek Kiernan <derek.kiernan@xilinx.com>,
        Dragan Cvetic <dragan.cvetic@xilinx.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Hans de Goede <hdegoede@redhat.com>,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-doc@vger.kernel.org, Andrew Scull <ascull@google.com>,
        Will Deacon <will@kernel.org>
Subject: Re: [PATCH v2 2/2] misc: dice: Add driver to forward secrets to
 userspace
Message-ID: <20211209193857.GA28088@duo.ucw.cz>
References: <20211209151123.3759999-1-dbrazdil@google.com>
 <20211209151123.3759999-3-dbrazdil@google.com>
 <YbIhaWC8b2DV5C7Y@kroah.com>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha1;
        protocol="application/pgp-signature"; boundary="dDRMvlgZJXvWKvBx"
Content-Disposition: inline
In-Reply-To: <YbIhaWC8b2DV5C7Y@kroah.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Precedence: bulk


--dDRMvlgZJXvWKvBx
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

Hi!

> > +	memzero_explicit(kaddr, dice_rmem->size);
> > +	devm_memunmap(dice_misc.this_device, kaddr);
>=20
> Do you really need to call memzero_explicit()?  This isn't "local"
> memory, if the compiler "optimizes away" a normal call, it would be
> _VERY_ broken.

For clearing secrets, I believe memzero_explicit is nice
documentation.

Best regards,
								Pavel
							=09
--=20
http://www.livejournal.com/~pavelmachek

--dDRMvlgZJXvWKvBx
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----

iF0EABECAB0WIQRPfPO7r0eAhk010v0w5/Bqldv68gUCYbJbUQAKCRAw5/Bqldv6
8n71AKCBLAVJBcsdGVg79i0seELqu5h7sQCgwIkrRK7FCzRulLPs8MlHx0SeYBg=
=GH6l
-----END PGP SIGNATURE-----

--dDRMvlgZJXvWKvBx--