From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wolfram Sang <w.sang@pengutronix.de>
Subject: Re: [PATCH net] mscan: zero accidentally copied register content
Date: Thu, 6 Oct 2011 11:24:57 +0200
Message-ID: <20111006092456.GB1974@pengutronix.de>
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Cc: Oliver Hartkopp <socketcan@hartkopp.net>,
	Linux Netdev List <netdev@vger.kernel.org>,
	Andre Naujoks <nautsch@gmail.com>
To: Wolfgang Grandegger <wg@grandegger.com>
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> Why do you want to change 16-bit accesses in general? They are faster
> than two 8 bit accesses.=20

Yup, was thinking the same.

>=20
> > IMHO this fix is small and clear and especially not risky. I wonder if
> > reworking the 16 bit register access is worth the effort?
>=20
> I would prefer:
>=20
>  	if (!(frame->can_id & CAN_RTR_FLAG)) {
>  		void __iomem *data =3D &regs->rx.dsr1_0;
>  		u16 *payload =3D (u16 *)frame->data;
> =20
>  		for (i =3D 0; i < frame->can_dlc / 2; i++) {
>  			*payload++ =3D in_be16(data);
>  			data +=3D 2 + _MSCAN_RESERVED_DSR_SIZE;
>  		}
> 		/* copy remaining byte */

if any

> 		if (frame->can_dlc & 1)
> 			frame->data[frame->can_dlc - 1] =3D in_8(data);

Ack.

Regards,

   Wolfram

--=20
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

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