Message-ID: <1348154575.4161.39.camel@jlt4.sipsolutions.net> (sfid-20120920_172225_370952_B9C0DBD7)
Subject: Re: regression: tethering fails in 3.5 with iwlwifi
From: Johannes Berg <johannes@sipsolutions.net>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: artem.bityutskiy@linux.intel.com,
	Eric Dumazet <edumazet@google.com>,
	linux-wireless@vger.kernel.org
Date: Thu, 20 Sep 2012 17:22:55 +0200
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On Thu, 2012-09-20 at 17:18 +0200, Eric Dumazet wrote:

> > Note I think the failing packets are dhcp packets, and connman seems to
> > use an AF_INET, SOCK_DGRAM, IPPROTO_UDP socket for those, and binds it
> > to the right device. I'd be quite surprised though if UDP code had
> > issues with paged Rx??

> You told me : socket(PF_PACKET, SOCK_RAW, htons(ETH_P_EAPOL))
> 
> So I looked at raw code.

and even found an issue. Artem wasn't really sure, but looking at his
information again it seems that the EAPOL packets (those on the raw
sockets) do go through, and then DHCP fails. In the printk he did for
me, I can see that the EAPOL packets are small enough to get pulled in
completely in iwlwifi, and the bigger DHCP packets (~600 bytes) only go
through if we linearize them.

johannes