From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Zefan Subject: Re: cgroups/netlink related rcu_dereference_check() without protection (2.6.35.4) Date: Thu, 02 Sep 2010 13:53:54 +0800 Message-ID: <4C7F3BF2.1050808@cn.fujitsu.com> References: <20100902014337.GC30324@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, Paul Menage To: Dave Jones Return-path: Received: from cn.fujitsu.com ([222.73.24.84]:64382 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751039Ab0IBFsu (ORCPT ); Thu, 2 Sep 2010 01:48:50 -0400 In-Reply-To: <20100902014337.GC30324@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: Dave Jones wrote: > I see this during boot on one of my boxes.. > > Dave > > INFO: suspicious rcu_dereference_check() usage. ] > --------------------------------------------------- > include/linux/cgroup.h:542 invoked rcu_dereference_check() without protection! > Will send out a fix soon. > other info that might help us debug this: > > > rcu_scheduler_active = 1, debug_locks = 0 > 1 lock held by swapper/1: > #0: (net_mutex){+.+.+.}, at: [] register_pernet_subsys+0x17/0x34 > > stack backtrace: > Pid: 1, comm: swapper Not tainted 2.6.35.4-15.fc14.i686.PAE #1 > Call Trace: > [] ? printk+0x25/0x2e > [] lockdep_rcu_dereference+0x7d/0x86 > [] sock_update_classid+0x6c/0x8e > [] sk_alloc+0x5f/0x6a > [] __netlink_create+0x2a/0x90 > [] netlink_kernel_create+0x5f/0x14f > [] rtnetlink_net_init+0x23/0x3b > [] ? rtnetlink_rcv+0x0/0x27 > [] ops_init+0xda/0xe9 > [] register_pernet_operations+0x84/0xee > [] register_pernet_subsys+0x23/0x34 > [] rtnetlink_init+0x42/0xe0 > [] netlink_proto_init+0xee/0x103 > [] ? netlink_proto_init+0x0/0x103 > [] do_one_initcall+0x62/0x170 > [] kernel_init+0x1b9/0x23a > [] ? kernel_init+0x0/0x23a > [] kernel_thread_helper+0x6/0x10 > > >