From: Maxime Bizon <mbizon@freebox.fr>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "Måns Rullgård" <mans@mansr.com>,
"Russell King - ARM Linux" <linux@arm.linux.org.uk>,
netdev@vger.kernel.org, "David Laight" <David.Laight@ACULAB.COM>,
"Jon Masters" <jonathan@jonmasters.org>,
linux-arm-kernel@lists.infradead.org
Subject: Re: alignment faults in 3.6
Date: Thu, 11 Oct 2012 13:47:35 +0200 [thread overview]
Message-ID: <1349956055.1232.9.camel@sakura.staff.proxad.net> (raw)
In-Reply-To: <1349954899.21172.8728.camel@edumazet-glaptop>
On Thu, 2012-10-11 at 13:28 +0200, Eric Dumazet wrote:
> You probably are aware that a driver can use :
>
> - a fragment to hold the frame given by the hardware, with whatever
> alignment is needed by the hardware.
>
> Then allocate an skb with enough room (128 bytes) to pull the headers as
> needed later.
>
> skb = netdev_alloc_skb_ip_align(dev, 128);
What happen at tx time, supposing that same hardware cannot do SG ?
Aren't we going to memcpy the data into the head ?
--
Maxime
next prev parent reply other threads:[~2012-10-11 11:47 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
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2012-10-11 2:27 ` alignment faults in 3.6 Måns Rullgård
2012-10-11 2:34 ` Jon Masters
2012-10-11 8:21 ` David Laight
2012-10-11 8:53 ` Russell King - ARM Linux
2012-10-11 9:45 ` Måns Rullgård
2012-10-11 10:00 ` Eric Dumazet
2012-10-11 10:20 ` Måns Rullgård
2012-10-11 10:22 ` Eric Dumazet
2012-10-11 10:32 ` Russell King - ARM Linux
2012-10-11 10:49 ` Eric Dumazet
2012-10-11 10:56 ` Maxime Bizon
2012-10-11 11:28 ` Eric Dumazet
2012-10-11 11:47 ` Maxime Bizon [this message]
2012-10-11 11:54 ` Eric Dumazet
2012-10-11 12:00 ` Eric Dumazet
2012-10-11 12:51 ` Maxime Bizon
2012-10-11 12:59 ` Eric Dumazet
2012-10-11 12:28 ` Arnd Bergmann
2012-10-11 12:40 ` Eric Dumazet
2012-10-11 13:20 ` Rob Herring
2012-10-11 13:32 ` Måns Rullgård
2012-10-11 13:35 ` Arnd Bergmann
2012-10-11 13:47 ` Eric Dumazet
2012-10-11 15:23 ` Rob Herring
2012-10-11 15:39 ` David Laight
2012-10-11 16:18 ` Måns Rullgård
2012-10-12 8:11 ` Arnd Bergmann
2012-10-12 9:03 ` Russell King - ARM Linux
2012-10-12 10:04 ` Eric Dumazet
2012-10-12 12:24 ` Russell King - ARM Linux
2012-10-12 11:00 ` Måns Rullgård
2012-10-12 11:07 ` Russell King - ARM Linux
2012-10-12 11:18 ` Måns Rullgård
2012-10-12 11:44 ` Russell King - ARM Linux
2012-10-12 12:08 ` Eric Dumazet
2012-10-12 14:22 ` Benjamin LaHaise
2012-10-12 14:36 ` David Laight
2012-10-12 14:48 ` Eric Dumazet
2012-10-12 15:00 ` Benjamin LaHaise
2012-10-12 15:04 ` Ben Hutchings
2012-10-12 15:47 ` David Laight
2012-10-12 16:13 ` Ben Hutchings
2012-10-12 12:16 ` Måns Rullgård
2012-10-12 11:19 ` Russell King - ARM Linux
2012-10-11 16:15 ` Eric Dumazet
2012-10-11 16:59 ` Catalin Marinas
2012-10-11 10:16 ` David Laight
2012-10-11 10:46 ` Måns Rullgård
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