Return-path: Received: from 128-177-27-249.ip.openhosting.com ([128.177.27.249]:59489 "EHLO jmalinen.user.openhosting.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753552AbZBEM15 (ORCPT ); Thu, 5 Feb 2009 07:27:57 -0500 Date: Thu, 5 Feb 2009 14:26:26 +0200 From: Jouni Malinen To: Johannes Berg Cc: Dan Williams , Samuel Ortiz , John Linville , Reinette Chatre , linux-wireless@vger.kernel.org Subject: Re: [PATCH RFC] mac80211: Filter scan results Message-ID: <20090205122626.GA19117@jm.kir.nu> (sfid-20090205_132800_234719_5723D2D9) References: <20090204150857.GA5069@sortiz.org> <1233789837.24227.19.camel@localhost.localdomain> <1233790539.7390.23.camel@johannes.local> <20090205084407.GA11126@jm.kir.nu> <20090205111058.GA16422@jm.kir.nu> <1233834907.3931.4.camel@johannes.local> <20090205120730.GA18339@jm.kir.nu> <1233835854.3931.18.camel@johannes.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1233835854.3931.18.camel@johannes.local> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Thu, Feb 05, 2009 at 01:10:54PM +0100, Johannes Berg wrote: > Yeah, the truncation is a little worrying. I doubt any program but > wpa_supplicant is prepared to handle that. Should we completely remove > the entry, and add some new/custom piece to stream that indicates that > we had to truncate here? Well, the truncation is partly an artifact of the way iwe_stream_* helpers work and I would expect all drivers to be doing this already (should they support large enough number of BSSes to hit the limit). If I have understood correctly, truncation happens between events, i.e., no event (struct iw_event) itself is truncated; some events are just missing from a BSS. As such, I would expect more or less all application to handle that one way or another. They may assume the network does not support WPA etc. based on some iw_events missing, but that should be about it. It would be somewhat cleaner to truncate between BSSes instead of between iw_events, but it would be some more code (remember the length before starting to add new BSS and use it if truncations was detected). I don't think I would bother with custom iw_event stating that truncation happened since I do not see much use for it in wpa_supplicant. It could be of some use for someone running iwlist scan manually. -- Jouni Malinen PGP id EFC895FA