From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Jones Subject: net/ipv6/ip6_flowlabel.c:543 suspicious rcu_dereference_check() usage! Date: Tue, 2 Feb 2016 14:59:33 -0500 Message-ID: <20160202195933.GA6302@codemonkey.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: netdev@vger.kernel.org Return-path: Received: from arcturus.aphlor.org ([188.246.204.175]:57510 "EHLO arcturus.aphlor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932078AbcBBT7h (ORCPT ); Tue, 2 Feb 2016 14:59:37 -0500 Received: from [209.6.119.210] (helo=wopr.kernelslacker.org) by arcturus.aphlor.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.86) (envelope-from ) id 1aQh6s-0000jq-W7 for netdev@vger.kernel.org; Tue, 02 Feb 2016 19:59:35 +0000 Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: =============================== [ INFO: suspicious RCU usage. ] 4.5.0-rc2-think+ #2 Tainted: G W ------------------------------- net/ipv6/ip6_flowlabel.c:543 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 1 2 locks held by trinity-c0/21982: #0: (sk_lock-AF_INET6){+.+.+.}, at: [] do_ipv6_setsockopt.isra.5+0x1bc/0x1c20 #1: (ip6_sk_fl_lock){+.....}, at: [] ipv6_flowlabel_opt+0x584/0x1b00 stack backtrace: CPU: 1 PID: 21982 Comm: trinity-c0 Tainted: G W 4.5.0-rc2-think+ #2 ffffffffb1821f20 00000000e98d3751 ffff88032ccaf798 ffffffffb076bd50 0000000041b58ab3 ffffffffb19d0db1 ffffffffb076bca5 0000000000000001 ffff8803011308e8 00000000e98d3751 ffff88032ccaf770 0000000000000003 Call Trace: [] dump_stack+0xab/0x11b [] ? _atomic_dec_and_lock+0x95/0x95 [] lockdep_rcu_suspicious+0xe6/0x100 [] ipv6_flowlabel_opt+0x62b/0x1b00 [] ? ipv6_flowlabel_opt_get+0x6b0/0x6b0 [] ? preempt_count_sub+0x1a/0x140 [] ? mark_held_locks+0xc8/0x140 [] ? __local_bh_enable_ip+0x64/0xc0 [] ? lock_sock_nested+0x5a/0xe0 [] ? trace_hardirqs_on+0xd/0x10 [] ? __local_bh_enable_ip+0x64/0xc0 [] ? lock_sock_nested+0xa9/0xe0 [] do_ipv6_setsockopt.isra.5+0xbc4/0x1c20 [] ? debug_lockdep_rcu_enabled.part.34+0x1f/0x40 [] ? ip6_ra_control+0x1d0/0x1d0 [] ? mark_lock+0xf4/0xc90 [] ? print_usage_bug+0x520/0x520 [] ? print_usage_bug+0x520/0x520 [] ? native_sched_clock+0x69/0x160 [] ? __lock_acquire+0x7ee/0x2ec0 [] ? mark_lock+0xf4/0xc90 [] ? print_usage_bug+0x520/0x520 [] ? debug_check_no_locks_freed+0x200/0x200 [] ? __lock_acquire+0x7ee/0x2ec0 [] ? preempt_count_sub+0xc9/0x140 [] ? debug_smp_processor_id+0x17/0x20 [] ? get_lock_stats+0x4e/0xf0 [] ? preempt_count_sub+0xc9/0x140 [] ? trace_hardirqs_off_caller+0x73/0x150 [] ? trace_hardirqs_off+0xd/0x10 [] ? __acct_update_integrals+0x108/0x260 [] ? taskstats_exit+0x5f0/0x5f0 [] ? debug_smp_processor_id+0x17/0x20 [] ? get_lock_stats+0x4e/0xf0 [] ? preempt_count_sub+0xc9/0x140 [] ? account_user_time+0x141/0x200 [] ipv6_setsockopt+0x31/0xe0 [] tcp_setsockopt+0x71/0xd0 [] sock_common_setsockopt+0x6c/0xb0 [] SyS_setsockopt+0x116/0x200 [] ? SyS_recv+0x20/0x20 [] ? int_ret_from_sys_call+0x52/0x9f [] ? trace_hardirqs_on_thunk+0x17/0x19 [] entry_SYSCALL_64_fastpath+0x12/0x6b