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Message-ID: <29ea34917cbfabf2b98b4957b7770683f5994873.camel@linux.intel.com>
Subject: Re: [PATCH v10 14/14] dmaengine: idxd: Add support for device/wq
 defaults
From:   Tom Zanussi <tom.zanussi@linux.intel.com>
To:     "Yu, Fenghua" <fenghua.yu@intel.com>,
        "herbert@gondor.apana.org.au" <herbert@gondor.apana.org.au>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "vkoul@kernel.org" <vkoul@kernel.org>
Cc:     "Jiang, Dave" <dave.jiang@intel.com>,
        "Luck, Tony" <tony.luck@intel.com>,
        "Feghali, Wajdi K" <wajdi.k.feghali@intel.com>,
        "Guilford, James" <james.guilford@intel.com>,
        "Sridhar, Kanchana P" <kanchana.p.sridhar@intel.com>,
        "Gopal, Vinodh" <vinodh.gopal@intel.com>,
        "Cabiddu, Giovanni" <giovanni.cabiddu@intel.com>,
        "pavel@ucw.cz" <pavel@ucw.cz>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
        "dmaengine@vger.kernel.org" <dmaengine@vger.kernel.org>
Date:   Thu, 30 Nov 2023 09:18:17 -0600
In-Reply-To: <IA1PR11MB6097D7EE44240E62DEA9AC769B82A@IA1PR11MB6097.namprd11.prod.outlook.com>
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Hi Fenghua,

On Thu, 2023-11-30 at 00:31 +0000, Yu, Fenghua wrote:
> Hi, Tom,
>=20
> > From: Tom Zanussi <tom.zanussi@linux.intel.com>
> > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0/* set name to "iaa_cryp=
to" */
> > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0memset(wq->name, 0, WQ_N=
AME_SIZE + 1);
> > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0strscpy(wq->name, "iaa_c=
rypto", WQ_NAME_SIZE + 1);
> > >=20
> > > Is strcpy(wq->name, "iaa_crypto") simpler than memset() and
> > > strscpy()?
> >=20
> > That's what I originally had, but checkpatch complained about it,
> > suggesting
> > strscpy, so I changed it to make checkpatch happy.
>=20
> Why is size WQ_NAME_SIZE+1 instead of WQ_NAME_SIZE? Will
> WQ_NAME_SIZE+1 cause mem corruption because wq->name is defined as a
> string with WQ_NAME_SIZE?

No, wq->name actually is:

        char name[WQ_NAME_SIZE + 1];

This code is doing the same thing as elsewhere in the idxd driver
except instead of sprintf() it uses strscpy().

> >=20
> > >=20
> > > > +
> > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0/* set driver_name to "c=
rypto" */
> > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0memset(wq->driver_name, =
0, DRIVER_NAME_SIZE + 1);
> > > > +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0strscpy(wq->driver_name,=
 "crypto", DRIVER_NAME_SIZE +
> > > > 1);
> > >=20
> > > Is strcpy(wq->driver_name, "crypto") simpler?
> >=20
> > Same here.
>=20
> Ditto.
>=20

Same.

Tom

> Thanks.
>=20
> -Fenghua