Return-path: Received: from smtp.nokia.com ([192.100.122.230]:64046 "EHLO mgw-mx03.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756352Ab0FHVJY convert rfc822-to-8bit (ORCPT ); Tue, 8 Jun 2010 17:09:24 -0400 From: To: CC: , , Date: Tue, 8 Jun 2010 23:09:02 +0200 Subject: RE: [PATCHv2] mac80211: Fix circular locking dependency in ARP filter handling Message-ID: References: <1276002335-18600-1-git-send-email-juuso.oikarinen@nokia.com>,<1276002863.3706.131.camel@jlt3.sipsolutions.net> In-Reply-To: <1276002863.3706.131.camel@jlt3.sipsolutions.net> Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: From: ext Johannes Berg [johannes@sipsolutions.net] > >On Tue, 2010-06-08 at 16:05 +0300, Juuso Oikarinen wrote: > >> + promisc = sdata->flags & IEEE80211_SDATA_PROMISC; >> + if (promisc) >> + bss_conf->arp_filter_enabled = 0; >> + else >> + bss_conf->arp_filter_enabled = sdata->arp_filter_state; > >bss_conf->arp_filter_enabled = !promisc && sdata->arp_filter_state; > >? > >Or if not, use false instead of 0 please. > Yes, sure I can change this. My home WLAN is giving me a headache, so I can't seem to access my work machine just now, but I began to wonder if I managed to create the same locking problem in this patch I had before. To traverse the interface list we need to acquire a lock - either the mutex for the iflist (which seems not to be an option as we also need the mgd mutex - to be locked after the iflist mutex) or the rtnl lock, which I chose to acquire. I quess the filter reconfig work is in the same mac80211 workqueue as the rest of the stuff, so the rtnl lock problem is there again. -Juuso >johannes