From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754522Ab1HNQJA (ORCPT ); Sun, 14 Aug 2011 12:09:00 -0400 Received: from cantor2.suse.de ([195.135.220.15]:36732 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754483Ab1HNQIz (ORCPT ); Sun, 14 Aug 2011 12:08:55 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Fri Aug 12 14:05:57 2011 Message-Id: <20110812210557.190724106@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Fri, 12 Aug 2011 14:04:43 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Stephen Hemminger , "David S. Miller" Subject: [58/90] net: allow netif_carrier to be called safely from IRQ In-Reply-To: <20110812210626.GA4725@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.0-stable review patch. If anyone has any objections, please let us know. ------------------ From: stephen hemminger [ Upstream commit 1821f7cd65ad9ea56580b830ac79bf4c4fef59cb ] As reported by Ben Greer and Froncois Romieu. The code path in the netif_carrier code leads it to try and disable a late workqueue to reenable it immediately netif_carrier_on -> linkwatch_fire_event -> linkwatch_schedule_work -> cancel_delayed_work -> del_timer_sync If __cancel_delayed_work is used instead then there is no problem of waiting for running linkwatch_event. There is a race between linkwatch_event running re-scheduling but it is harmless to schedule an extra scan of the linkwatch queue. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/core/link_watch.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/core/link_watch.c +++ b/net/core/link_watch.c @@ -126,7 +126,7 @@ static void linkwatch_schedule_work(int return; /* It's already running which is good enough. */ - if (!cancel_delayed_work(&linkwatch_work)) + if (!__cancel_delayed_work(&linkwatch_work)) return; /* Otherwise we reschedule it again for immediate execution. */