From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stanislaw Gruszka Subject: [PATCH] net: fix unreg list corruption in dev_deactivate() Date: Sun, 20 Feb 2011 12:34:29 +0100 Message-ID: <20110220113429.GA27047@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Octavian Purdila , Eric Dumazet , "David S. Miller" To: netdev@vger.kernel.org Return-path: Received: from mx3.wp.pl ([212.77.101.7]:48070 "EHLO mx3.wp.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751528Ab1BTLfJ (ORCPT ); Sun, 20 Feb 2011 06:35:09 -0500 Received: from ip-78-102-112-198.net.upcbroadband.cz (HELO localhost) (stf_xl@wp.pl@[78.102.112.198]) (envelope-sender ) by smtp.wp.pl (WP-SMTPD) with AES128-SHA encrypted SMTP for ; 20 Feb 2011 12:35:05 +0100 Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: Patch fix issue introduced by 443457242beb6716b43db4d62fe148eab5515505 "net: factorize sync-rcu call in unregister_netdevice_many". It manifest on my system by following warning when removing usb wireless device. [ 3539.368139] WARNING: at lib/list_debug.c:53 __list_del_entry+0x62/0x71() [ 3539.368149] list_del corruption. prev->next should be f035e05c, but was f1ce670c [ 3539.368242] Call Trace: [ 3539.368254] [] ? warn_slowpath_common+0x6a/0x7f [ 3539.368262] [] ? __list_del_entry+0x62/0x71 [ 3539.368269] [] ? warn_slowpath_fmt+0x2b/0x2f [ 3539.368276] [] ? __list_del_entry+0x62/0x71 [ 3539.368286] [] ? unregister_netdevice_queue+0x41/0x6e [ 3539.368322] [] ? ieee80211_remove_interfaces+0x7b/0x9a [mac80211] [ 3539.368348] [] ? ieee80211_unregister_hw+0x48/0xf9 [mac80211] [ 3539.368363] [] ? rt2x00lib_remove_dev+0x76/0xd1 [rt2x00lib] [ 3539.368372] [] ? rt2x00usb_disconnect+0x29/0x8c [rt2x00usb] [ 3539.368382] [] ? usb_unbind_interface+0x48/0xfd I'm no longer seeing warning with patch applied. Signed-off-by: Stanislaw Gruszka --- I did not try review related code. I think someone who understand it, should audit it carefully to exclude similar issues. Adding dev->unreg_list to various local list, when device will not gonna be destroyed looks really fishy. diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 34dc598..1bc6980 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -839,6 +839,7 @@ void dev_deactivate(struct net_device *dev) list_add(&dev->unreg_list, &single); dev_deactivate_many(&single); + list_del(&single); } static void dev_init_scheduler_queue(struct net_device *dev,