IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready device bridge_slave_1 left promiscuous mode bridge0: port 2(bridge_slave_1) entered disabled state device bridge_slave_0 left promiscuous mode bridge0: port 1(bridge_slave_0) entered disabled state INFO: task syz-executor0:13041 blocked for more than 140 seconds. Not tainted 4.20.0+ #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor0 D23960 13041 7553 0x80000006 Call Trace: context_switch kernel/sched/core.c:2831 [inline] __schedule+0x897/0x1e90 kernel/sched/core.c:3472 schedule+0xfe/0x350 kernel/sched/core.c:3516 __rwsem_down_write_failed_common+0xa4d/0x1620 kernel/locking/rwsem-xadd.c:577 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:606 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0xa5/0x130 kernel/locking/rwsem.c:72 deactivate_super fs/super.c:359 [inline] deactivate_super+0x2a9/0x320 fs/super.c:356 cleanup_mnt+0xbf/0x160 fs/namespace.c:1098 __cleanup_mnt+0x16/0x20 fs/namespace.c:1105 task_work_run+0x1f4/0x2b0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x19d6/0x2650 kernel/exit.c:867 do_group_exit+0x177/0x430 kernel/exit.c:970 get_signal+0x8b4/0x19b0 kernel/signal.c:2517 do_signal+0x91/0x1e80 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x2f7/0x3b0 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x696/0x800 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: Bad RIP value. RSP: 002b:00007fe4ffc6bcf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000073bf08 RCX: 0000000000457ec9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000073bf08 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000073bf0c R13: 00007ffcb31e49bf R14: 00007fe4ffc6c9c0 R15: 000000000073bf0c Showing all locks held in the system: 3 locks held by kworker/1:0/17: #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: __write_once_size include/linux/compiler.h:218 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0xbc7/0x1ce0 kernel/workqueue.c:2124 #1: 00000000b6931c7d ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0xc1d/0x1ce0 kernel/workqueue.c:2128 #2: 000000001357ae93 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 5 locks held by kworker/u4:1/21: 2 locks held by kworker/u4:2/26: #0: 0000000075569860 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1149 [inline] #0: 0000000075569860 (&rq->lock){-.-.}, at: __schedule+0x21e/0x1e90 kernel/sched/core.c:3410 #1: 00000000072b5b13 (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:428 [inline] #1: 00000000072b5b13 (rcu_read_lock){....}, at: update_curr+0x362/0xbc0 kernel/sched/fair.c:829 4 locks held by kworker/u4:3/119: 1 lock held by khungtaskd/1040: #0: 00000000072b5b13 (rcu_read_lock){....}, at: debug_show_all_locks+0xc6/0x41d kernel/locking/lockdep.c:4389 1 lock held by rsyslogd/7426: #0: 00000000919c455b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1b3/0x1f0 fs/file.c:795 2 locks held by getty/7516: #0: 00000000c63c78af (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000016f529f5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7517: #0: 00000000147656be (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000d3449a02 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7518: #0: 00000000f02818a0 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000ccdc8ae5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7519: #0: 000000002546ecde (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000b4e6b315 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7520: #0: 00000000decab218 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000ae38060e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7521: #0: 00000000d4dd1db9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000f89e1a8d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 2 locks held by getty/7522: #0: 00000000ca16d7a4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008464e48f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x30a/0x1eb0 drivers/tty/n_tty.c:2154 3 locks held by kworker/0:3/7566: #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: __write_once_size include/linux/compiler.h:218 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 000000001091e580 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0xbc7/0x1ce0 kernel/workqueue.c:2124 #1: 00000000e0768e6a ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0xc1d/0x1ce0 kernel/workqueue.c:2128 #2: 000000001357ae93 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 3 locks held by kworker/1:4/7572: #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: __write_once_size include/linux/compiler.h:218 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: process_one_work+0xbc7/0x1ce0 kernel/workqueue.c:2124 #1: 00000000957919d0 ((linkwatch_work).work){+.+.}, at: process_one_work+0xc1d/0x1ce0 kernel/workqueue.c:2128 #2: 000000001357ae93 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor0/13041: #0: 000000007c15b1ec (&type->s_umount_key#48){++++}, at: deactivate_super fs/super.c:359 [inline] #0: 000000007c15b1ec (&type->s_umount_key#48){++++}, at: deactivate_super+0x2a9/0x320 fs/super.c:356 3 locks held by kworker/1:1/17720: #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: __write_once_size include/linux/compiler.h:218 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 000000008f9cdfa6 ((wq_completion)"events"){+.+.}, at: process_one_work+0xbc7/0x1ce0 kernel/workqueue.c:2124 #1: 00000000b14c8869 (deferred_process_work){+.+.}, at: process_one_work+0xc1d/0x1ce0 kernel/workqueue.c:2128 #2: 000000001357ae93 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor5/21851: #0: 000000001357ae93 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 000000001357ae93 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x425/0xc30 net/core/rtnetlink.c:5122 1 lock held by syz-executor3/21852: #0: 000000001357ae93 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 000000001357ae93 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x425/0xc30 net/core/rtnetlink.c:5122 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1040 Comm: khungtaskd Not tainted 4.20.0+ #3 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1db/0x2d0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xbd2/0x10b0 kernel/hung_task.c:289 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.889 msecs CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 4.20.0+ #3 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:__raw_read_unlock include/linux/rwlock_api_smp.h:225 [inline] RIP: 0010:_raw_read_unlock+0x1/0x50 kernel/locking/spinlock.c:248 Code: 01 00 00 00 31 f6 e8 de d4 71 f9 41 bc 01 00 00 00 58 44 89 e0 48 8d 65 f0 5b 41 5c 5d c3 e8 85 81 0e f9 eb bc 0f 1f 40 00 55 01 00 00 00 48 89 e5 41 54 49 89 fc 48 83 c7 18 48 8b 55 08 e8 RSP: 0018:ffff8880a95ae698 EFLAGS: 00000293 RAX: ffff8880a95a2580 RBX: ffff8880a95ae7e0 RCX: ffffffff86d04a69 RDX: 0000000000000000 RSI: ffffffff86d04662 RDI: ffff8880a3ea0f40 RBP: ffff8880a95ae868 R08: ffff8880a95aea50 R09: ffffed10147d41e9 R10: ffffed10147d41e8 R11: ffff8880a3ea0f43 R12: ffff8880a035f2c0 R13: dffffc0000000000 R14: ffff888094118200 R15: ffff8880a95aea58 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000457e9f CR3: 00000000951f4000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: fib6_clean_node+0x453/0x660 net/ipv6/ip6_fib.c:2002 fib6_walk_continue+0x4b3/0x8e0 net/ipv6/ip6_fib.c:1924 fib6_walk+0x9d/0x100 net/ipv6/ip6_fib.c:1972 fib6_clean_tree+0x22a/0x340 net/ipv6/ip6_fib.c:2051 __fib6_clean_all+0x216/0x430 net/ipv6/ip6_fib.c:2067 fib6_clean_all+0x2b/0x40 net/ipv6/ip6_fib.c:2078 rt6_sync_down_dev+0x17e/0x1b0 net/ipv6/route.c:4039 rt6_disable_ip+0x80/0x730 net/ipv6/route.c:4044 addrconf_ifdown+0x13e/0x15e0 net/ipv6/addrconf.c:3669 addrconf_notify+0x629/0x25f0 net/ipv6/addrconf.c:3594 notifier_call_chain+0x179/0x380 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739 call_netdevice_notifiers_extack net/core/dev.c:1751 [inline] call_netdevice_notifiers net/core/dev.c:1765 [inline] dev_close_many+0x42e/0x890 net/core/dev.c:1508 rollback_registered_many+0x544/0x1370 net/core/dev.c:8079 unregister_netdevice_many.part.0+0x8e/0x470 net/core/dev.c:9207 unregister_netdevice_many net/core/dev.c:9206 [inline] default_device_exit_batch+0x4c9/0x5f0 net/core/dev.c:9676 ops_exit_list.isra.0+0x105/0x160 net/core/net_namespace.c:156 cleanup_net+0x51d/0xb10 net/core/net_namespace.c:551 process_one_work+0xd0c/0x1ce0 kernel/workqueue.c:2153 worker_thread+0x143/0x14a0 kernel/workqueue.c:2296 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352