From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from s3.sipsolutions.net ([5.9.151.49]:47892 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751608AbcA0MRX (ORCPT ); Wed, 27 Jan 2016 07:17:23 -0500 Message-ID: <1453897040.2351.3.camel@sipsolutions.net> (sfid-20160127_131726_366051_5927EBBD) Subject: Re: [PATCH] wext: fix message delay/ordering From: Johannes Berg To: linux-wireless@vger.kernel.org Cc: Beniamino Galvani Date: Wed, 27 Jan 2016 13:17:20 +0100 In-Reply-To: <1453896850-22775-1-git-send-email-johannes@sipsolutions.net> (sfid-20160127_131419_031860_43892E09) References: <1453896850-22775-1-git-send-email-johannes@sipsolutions.net> (sfid-20160127_131419_031860_43892E09) Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, 2016-01-27 at 13:14 +0100, Johannes Berg wrote: >  > +static int wext_netdev_notifier_call(struct notifier_block *nb, > +      unsigned long state, void *ptr) > +{ > + /* > +  * When a netdev is unregistered, flush all pending messages > +  * to avoid them going out after the RTM_DELLINK, which can > +  * happen due to the schedule_work(). > +  */ > + if (state == NETDEV_UNREGISTER) > + wireless_nlevent_flush(); > It could be argued that the state check isn't really necessary and should be removed to avoid ordering issues with up/down vs. wext, but this fixes the really strange issue where you get an RTM_NEWLINK after RTM_DELLINK (with the same ifidx), and I don't see how any software would care much about the ordering otherwise. johannes