Return-path: Received: from stinky.trash.net ([213.144.137.162]:63139 "EHLO stinky.trash.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751234AbYGXKTv (ORCPT ); Thu, 24 Jul 2008 06:19:51 -0400 Message-ID: <48885743.8030505@trash.net> (sfid-20080724_121954_779159_81F751BE) Date: Thu, 24 Jul 2008 12:19:47 +0200 From: Patrick McHardy MIME-Version: 1.0 To: Tomas Winkler CC: David Miller , francois.valenduc@tvcablenet.be, akpm@linux-foundation.org, bugme-daemon@bugzilla.kernel.org, linux-wireless@vger.kernel.org, linville@tuxdriver.com, netdev@vger.kernel.org, jussi.kivilinna@mbnet.fi Subject: Re: [Bugme-new] [Bug 11144] New: dhcp doesn't work with iwl4965 References: <4887550B.2070704@tvcablenet.be> <4887555A.30605@trash.net> <48875B8C.2090800@trash.net> <20080723.142147.61941255.davem@davemloft.net> <48884451.1090703@trash.net> <1ba2fa240807240317g15f6ba84h91b513cce75975e9@mail.gmail.com> In-Reply-To: <1ba2fa240807240317g15f6ba84h91b513cce75975e9@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: Tomas Winkler wrote: > On Thu, Jul 24, 2008 at 11:58 AM, Patrick McHardy wrote: >> David Miller wrote: >>> From: Patrick McHardy >>> Date: Wed, 23 Jul 2008 18:25:48 +0200 >>> >>>> We can't fit them into the cb together, I don't see a way to >>>> shrink ieee80211_tx_info. >>>> >>>> Maybe one of the wireless folks can suggest something? Is it >>>> really necessary to pass the full struct ieee80211_tx_info >>>> through the qdisc layer, or could the struct be split? It >>>> needs to find a way to co-exist peacefully with qdiscs' >>>> skb->cb usage. >>> This is another area that got mangled up in the ->select_queue() >>> conversion of the WME bits, but in another aspect this problem >>> existed beforehand as well. >>> >>> Specifically, when RX packets get requeued out to transmit in >>> the code in net/mac80211/rx.c that resends packets back out the >>> wireless device by setting a bit in the SKB CB then calling >>> dev_queue_xmit(). >>> >>> That's completely illegal :-) >> It seems its doing even more illegal things that were also >> present previously. The ieee80211_master_start_xmit function >> expects to get a valid IEEE80211_SKB_CB, which means it >> expects it to survive through the entire qdisc layer. I'm >> not sure how packets get to the master device from the >> subifs though, so I might be wrong. >> > Isn't this time to make 802.11 native? You mean by making these things real skb members? I hope you're not talking about the entire 48 bytes? :)