From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [net-next-2.6 PATCH v2] net: zero kobject in rx_queue_release Date: Wed, 17 Nov 2010 12:29:49 -0800 (PST) Message-ID: <20101117.122949.98878193.davem@davemloft.net> References: <20101116163139.2084.20075.stgit@jf-dev1-dcblab> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, eric.dumazet@gmail.com, therbert@google.com To: john.r.fastabend@intel.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:52471 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932364Ab0KQU3Y (ORCPT ); Wed, 17 Nov 2010 15:29:24 -0500 In-Reply-To: <20101116163139.2084.20075.stgit@jf-dev1-dcblab> Sender: netdev-owner@vger.kernel.org List-ID: From: John Fastabend Date: Tue, 16 Nov 2010 08:31:39 -0800 > 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 Applied.