INFO: task kworker/u4:8:8321 blocked for more than 143 seconds. Not tainted 5.1.0-rc6+ #191 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:8 D24120 8321 2 0x80000000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 exp_funnel_lock kernel/rcu/tree_exp.h:308 [inline] synchronize_rcu_expedited+0x54e/0x5b0 kernel/rcu/tree_exp.h:758 synchronize_net+0x3b/0x60 net/core/dev.c:9263 dev_deactivate_many+0x46f/0xb60 net/sched/sch_generic.c:1221 __dev_close_many+0x13d/0x300 net/core/dev.c:1480 dev_close_many+0x25b/0x6f0 net/core/dev.c:1518 rollback_registered_many+0x43b/0xfd0 net/core/dev.c:8177 unregister_netdevice_many.part.0+0x1b/0x1f0 net/core/dev.c:9308 unregister_netdevice_many+0x3b/0x50 net/core/dev.c:9307 ip6gre_exit_batch_net+0x535/0x750 net/ipv6/ip6_gre.c:1608 ops_exit_list.isra.0+0x105/0x160 net/core/net_namespace.c:156 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:552 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 INFO: task syz-executor.2:4982 blocked for more than 143 seconds. Not tainted 5.1.0-rc6+ #191 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D26816 4982 7636 0x80000006 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76 cangw_pernet_exit+0x13/0x30 net/can/gw.c:1029 ops_exit_list.isra.0+0xb0/0x160 net/core/net_namespace.c:153 setup_net+0x400/0x740 net/core/net_namespace.c:332 copy_net_ns+0x1df/0x340 net/core/net_namespace.c:438 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:206 ksys_unshare+0x440/0x980 kernel/fork.c:2549 __do_sys_unshare kernel/fork.c:2617 [inline] __se_sys_unshare kernel/fork.c:2615 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2615 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458da9 Code: 05 0c cc 45 00 48 89 04 24 48 c7 44 24 08 01 00 00 00 e8 6a 3e fd ff 48 8b 44 24 18 48 89 04 24 e8 0c 3d fd ff 48 8d 05 e5 cb <45> 00 48 89 04 24 48 c7 44 24 08 01 00 00 00 e8 43 3e fd ff 48 8b RSP: 002b:00007f2febcdbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000458da9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2febcdc6d4 R13: 00000000004c7e4c R14: 00000000004de0c0 R15: 00000000ffffffff INFO: task syz-executor.2:5022 blocked for more than 143 seconds. Not tainted 5.1.0-rc6+ #191 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28352 5022 7636 0x80000006 Call Trace: context_switch kernel/sched/core.c:2877 [inline] __schedule+0x813/0x1cc0 kernel/sched/core.c:3518 schedule+0x92/0x180 kernel/sched/core.c:3562 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76 cangw_pernet_exit+0x13/0x30 net/can/gw.c:1029 ops_exit_list.isra.0+0xb0/0x160 net/core/net_namespace.c:153 setup_net+0x400/0x740 net/core/net_namespace.c:332 copy_net_ns+0x1df/0x340 net/core/net_namespace.c:438 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:206 ksys_unshare+0x440/0x980 kernel/fork.c:2549 __do_sys_unshare kernel/fork.c:2617 [inline] __se_sys_unshare kernel/fork.c:2615 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2615 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458da9 Code: 05 0c cc 45 00 48 89 04 24 48 c7 44 24 08 01 00 00 00 e8 6a 3e fd ff 48 8b 44 24 18 48 89 04 24 e8 0c 3d fd ff 48 8d 05 e5 cb <45> 00 48 89 04 24 48 c7 44 24 08 01 00 00 00 e8 43 3e fd ff 48 8b RSP: 002b:00007f2febc36c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000458da9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 000000000073c220 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2febc376d4 R13: 00000000004c7e4c R14: 00000000004de0c0 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1042: #0: 000000007015dca7 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5057 1 lock held by rsyslogd/7503: #0: 00000000aa30a38a (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/7594: #0: 00000000ec85ce42 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000b17984fd (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7595: #0: 00000000caa0bc16 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000006f85dfbe (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7596: #0: 000000000884f1c6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000000a9fddf1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7597: #0: 00000000504da2a6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000a280912f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7598: #0: 00000000c9eed20f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000244be391 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7599: #0: 000000002fc19534 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000005be11f2b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7600: #0: 00000000ba746ee7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000903c964c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 3 locks held by kworker/0:5/7667: #0: 00000000e29ee66e ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000e29ee66e ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000e29ee66e ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000e29ee66e ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000e29ee66e ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000e29ee66e ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000e29ee66e ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240 #1: 0000000071497545 ((addr_chk_work).work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244 #2: 0000000084b7f313 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76 4 locks held by kworker/u4:8/8321: #0: 00000000e7c54190 ((wq_completion)netns){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000e7c54190 ((wq_completion)netns){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000e7c54190 ((wq_completion)netns){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000e7c54190 ((wq_completion)netns){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000e7c54190 ((wq_completion)netns){+.+.}, at: set_work_data kernel/workqueue.c:619 [inline] #0: 00000000e7c54190 ((wq_completion)netns){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: 00000000e7c54190 ((wq_completion)netns){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240 #1: 000000003c53e59a (net_cleanup_work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244 #2: 0000000044b83cec (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0x960 net/core/net_namespace.c:519 #3: 0000000084b7f313 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76 2 locks held by syz-executor.2/4982: #0: 0000000044b83cec (pernet_ops_rwsem){++++}, at: copy_net_ns+0x1c0/0x340 net/core/net_namespace.c:434 #1: 0000000084b7f313 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76 2 locks held by syz-executor.2/5022: #0: 0000000044b83cec (pernet_ops_rwsem){++++}, at: copy_net_ns+0x1c0/0x340 net/core/net_namespace.c:434 #1: 0000000084b7f313 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:76 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1042 Comm: khungtaskd Not tainted 5.1.0-rc6+ #191 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+0x172/0x1f0 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:204 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:288 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: