From patchwork Tue Nov 16 06:59:06 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Fastabend X-Patchwork-Id: 71361 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id E9CBBB7110 for ; Tue, 16 Nov 2010 18:01:47 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933915Ab0KPHBn (ORCPT ); Tue, 16 Nov 2010 02:01:43 -0500 Received: from mga09.intel.com ([134.134.136.24]:19041 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933886Ab0KPHBm (ORCPT ); Tue, 16 Nov 2010 02:01:42 -0500 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga102.jf.intel.com with ESMTP; 15 Nov 2010 23:01:41 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.59,204,1288594800"; d="scan'208";a="574188288" Received: from unknown (HELO [127.0.0.1]) ([10.23.209.48]) by orsmga002.jf.intel.com with ESMTP; 15 Nov 2010 23:01:41 -0800 From: John Fastabend Subject: [net-next-2.6 PATCH] net: zero kobject in rx_queue_release To: davem@davemloft.net Cc: john.r.fastabend@intel.com, netdev@vger.kernel.org, eric.dumazet@gmail.com, therbert@google.com Date: Mon, 15 Nov 2010 22:59:06 -0800 Message-ID: <20101116065906.31611.36938.stgit@jf-dev1-dcblab> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org netif_set_real_num_rx_queues() can decrement and increment the number of rx queues. For example ixgbe does this as features and offloads are toggled. Presumably this could also happen across down/up on most devices if the available resources changed (cpu offlined). The kobject needs to be zero'd in this case so that the state is not preserved across kobject_put()/kobject_init_and_add(). This resolves the following error report. ixgbe 0000:03:00.0: eth2: NIC Link is Up 10 Gbps, Flow Control: RX/TX kobject (ffff880324b83210): tried to init an initialized object, something is seriously wrong. Pid: 1972, comm: lldpad Not tainted 2.6.37-rc18021qaz+ #169 Call Trace: [] kobject_init+0x3a/0x83 [] kobject_init_and_add+0x23/0x57 [] ? mark_lock+0x21/0x267 [] net_rx_queue_update_kobjects+0x63/0xc6 [] netif_set_real_num_rx_queues+0x5f/0x78 [] ixgbe_set_num_queues+0x1c6/0x1ca [ixgbe] [] ixgbe_init_interrupt_scheme+0x1e/0x79c [ixgbe] [] ixgbe_dcbnl_set_state+0x167/0x189 [ixgbe] Signed-off-by: John Fastabend --- net/core/net-sysfs.c | 9 +++++++-- 1 files changed, 7 insertions(+), 2 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 3ba526b..960c075 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -711,13 +711,18 @@ static void rx_queue_release(struct kobject *kobj) map = rcu_dereference_raw(queue->rps_map); - if (map) + if (map) { + rcu_assign_pointer(queue->rps_map, NULL); call_rcu(&map->rcu, rps_map_release); + } flow_table = rcu_dereference_raw(queue->rps_flow_table); - if (flow_table) + if (flow_table) { + rcu_assign_pointer(queue->rps_flow_table, NULL); call_rcu(&flow_table->rcu, rps_dev_flow_table_release); + } + memset(kobj, 0, sizeof(*kobj)); dev_put(queue->dev); }