From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-gw1-out.broadcom.com ([216.31.210.62]:39426 "EHLO mail-gw1-out.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751401AbaBZJH5 (ORCPT ); Wed, 26 Feb 2014 04:07:57 -0500 Message-ID: <530DAECD.8010405@broadcom.com> (sfid-20140226_100810_781254_A1F70BFB) Date: Wed, 26 Feb 2014 10:07:25 +0100 From: Arend van Spriel MIME-Version: 1.0 To: Johannes Berg CC: "John W. Linville" , linux-wireless Subject: Re: [PATCH 01/14] brcmfmac: add delay before unregistering the network device References: <1393356639-19169-1-git-send-email-arend@broadcom.com> <1393356639-19169-2-git-send-email-arend@broadcom.com> (sfid-20140225_203048_842452_A39499B6) <1393358376.4170.22.camel@jlt4.sipsolutions.net> In-Reply-To: <1393358376.4170.22.camel@jlt4.sipsolutions.net> Content-Type: text/plain; charset="UTF-8" Sender: linux-wireless-owner@vger.kernel.org List-ID: On 02/25/2014 08:59 PM, Johannes Berg wrote: > On Tue, 2014-02-25 at 20:30 +0100, Arend van Spriel wrote: >> Upon deleting the interface a cfg80211_disconnected() is called under >> rtnl_lock. Right after the unlocking the rtnl_lock we unregister the >> network device. This patch adds delay before unregister so cfg80211 >> can handle disconnect and notify wpa_supplicant. > >> + /* make sure cfg80211 can send disconnect event >> + * before unregistering the netdevice below. >> + */ >> + msleep(100); > > This has got to be one of the worst hacks I've seen in wireless so > far ... :) Did you see I removed a sleep as well in this patch :-p I just don't see how I can assure cfg80211 has actually done the disconnect work. If we don't do a cfg80211_disconnected() I get a WARN from the cfg80211 netdev notifier (or at least I did in previous kernel). Should we consider a clean solution, ie. modify cfg80211 for this scenario? Gr. AvS