Subject: Re: [PATCH/RFT] iwlagn: fix RX skb alignment
From: Johannes Berg <johannes@sipsolutions.net>
To: Tomas Winkler <tomasw@gmail.com>
Cc: John Linville <linville@tuxdriver.com>,
	reinette chatre <reinette.chatre@intel.com>,
	Marcel Holtmann <marcel@holtmann.org>,
	"Luis R. Rodriguez" <mcgrof@gmail.com>,
	"Rafael J. Wysocki" <rjw@sisk.pl>, Matt Mackall <mpm@selenic.com>,
	Christophe Dumez <dchris@gmail.com>, Zhu Yi <yi.zhu@intel.com>,
	Jan =?UTF-8?Q?V=C4=8Del=C3=A1k?= <vcelak.jan@seznam.cz>,
	Thomas Witt <witt_th@gmx.de>,
	linux-wireless <linux-wireless@vger.kernel.org>,
	Andres Freund <andres@anarazel.de>
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Date: Wed, 19 Nov 2008 14:12:27 +0100
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On Wed, 2008-11-19 at 14:09 +0100, Johannes Berg wrote:
> On Wed, 2008-11-19 at 15:02 +0200, Tomas Winkler wrote:
>=20
> > > Here's a thought: iwl_rx_queue_update_write_ptr doesn't synchronise t=
he
> > > pointer rxq->bd memory to the device. So if you have a platform that'=
s
> > > not cache coherent for IO devices (mine is) that might be a problem.
> >=20
> > Need to issue wmb() there or something like this?
>=20
> well rb is also dma memory, no? So you'd have to use dma_sync_ or
> something, just like with skb data, no?

or maybe not? I can't look into this today, sorry.

johannes

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