From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [Bugme-new] [Bug 38102] New: BUG kmalloc-2048: Poison
 overwritten
Date: Tue, 05 Jul 2011 18:47:21 +0200
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Cc: Alexey Zaytsev <alexey.zaytsev@gmail.com>,
	Michael =?ISO-8859-1?Q?B=FCsch?= <m@bues.ch>,
	Andrew Morton <akpm@linux-foundation.org>,
	netdev@vger.kernel.org, Gary Zambrano <zambrano@broadcom.com>,
	bugme-daemon@bugzilla.kernel.org,
	"David S. Miller" <davem@davemloft.net>,
	Pekka Pietikainen <pp@ee.oulu.fi>,
	Florian Schirmer <jolt@tuxbox.org>,
	Felix Fietkau <nbd@openwrt.org>, Michael Buesch <mb@bu3sch.de>
To: Neil Horman <nhorman@tuxdriver.com>
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Le mardi 05 juillet 2011 =C3=A0 12:42 -0400, Neil Horman a =C3=A9crit :
> On Tue, Jul 05, 2011 at 06:12:32PM +0200, Eric Dumazet wrote:

> > So all descriptors before prod are guaranteed to be ready for host
> > consume... Fact that a dma access is running on 'next descriptor' s=
hould
> > be irrelevant.
> >=20
> But we handle more than one descriptor per b44_rx call - theres a whi=
le loop in
> there where we do advance to the next descriptor.

Yes, but we advance up to 'prod', which is the very last safe
descriptor.

If hardware advertises descriptor X being ready to be handled by host,
while DMA on this X descriptor is not yet finished, this would be a
really useless hardware ;)