Return-path: Received: from s3.sipsolutions.net ([144.76.43.152]:40066 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752157Ab3FEHxF (ORCPT ); Wed, 5 Jun 2013 03:53:05 -0400 Message-ID: <1370418780.8920.19.camel@jlt4.sipsolutions.net> (sfid-20130605_095309_615193_752A2BA5) Subject: Re: [PATCH v8] cfg80211: P2P find phase offload From: Johannes Berg To: Vladimir Kondratiev Cc: Jouni Malinen , "Peer, Ilan" , "linux-wireless@vger.kernel.org" , "Rodriguez, Luis" , "John W . Linville" Date: Wed, 05 Jun 2013 09:53:00 +0200 In-Reply-To: <2109265.XIVW7kjjZK@lx-vladimir> References: <8887AA04B7EC49479420AE48C5F94A930EF6C0AA@NASANEXD02D.na.qualcomm.com> <2442077.aHiBPHBLmq@lx-vladimir> <20130604183023.GB6172@jouni.qca.qualcomm.com> <2109265.XIVW7kjjZK@lx-vladimir> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, 2013-06-05 at 10:10 +0300, Vladimir Kondratiev wrote: > Then, I think it would be appropriate to say following in the comment for > start_p2p_find (no code changes, it is only expectations for the friver behavior): > > While performing P2P discovery, driver should report all received > probe-request and probe-response frames via cfg80211_rx_mgmt, > accordingly to the rx mgmt filter, as set by mgmt_frame_register(). Well, realistically there will be a frame registration for probe requests, so stating that is kinda pointless, but OK. > When reporting probes, driver/firmware may do its best to filter out > probes that would not be replied with probe-resp accordingly to the > P2P rules for active device configuration. This I think should be more specific. "[W]ould not be replied" is clearly one step, but in an environment where you actually want to offload the P2P probe responses that is pretty much useless. I'd rather say something like: --- When probe response offload it supported, the device should not report probe requests to the host that it already responded to. It must report (and therefore not respond to) probe requests that indicate the sending device is in active PBC mode (specifically, <...add more details...>). It may also drop invalid or malformed probe requests or ones that would not be replied to for other reasons. --- I think this would be a reasonable tradeoff. It means that if a probe request is actually reported, wpa_supplicant must reply to it, and we don't have to get into the business of having to decide whether or not it needs to respond. Alternatively, we could specify that the device _must_ respond if offload is supported, and then report it. However, we need to clearly specify this so that we don't get two responses, one from the device and one from wpa_s. If there's no way to specify this, we need to introduce a "reply already sent" flag into the frame reporting. johannes