INFO: task kworker/u4:1:21 blocked for more than 143 seconds. Not tainted 5.2.0-rc5+ #56 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:1 D25232 21 2 0x80004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 exp_funnel_lock kernel/rcu/tree_exp.h:309 [inline] synchronize_rcu_expedited+0x54e/0x5b0 kernel/rcu/tree_exp.h:790 synchronize_net+0x3b/0x60 net/core/dev.c:9269 rollback_registered_many+0xb2c/0xfc0 net/core/dev.c:8237 unregister_netdevice_many.part.0+0x1b/0x1f0 net/core/dev.c:9314 unregister_netdevice_many+0x3b/0x50 net/core/dev.c:9313 ip_tunnel_delete_nets+0x41e/0x5f0 net/ipv4/ip_tunnel.c:1113 ipgre_exit_batch_net+0x23/0x30 net/ipv4/ip_gre.c:993 ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:157 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:553 process_one_work+0x989/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x354/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task syz-executor.5:23578 blocked for more than 143 seconds. Not tainted 5.2.0-rc5+ #56 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D25376 23578 8686 0x80004004 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3568 __mutex_lock_common kernel/locking/mutex.c:1003 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1073 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 cangw_pernet_exit+0x13/0x30 net/can/gw.c:1029 ops_exit_list.isra.0+0xaa/0x150 net/core/net_namespace.c:154 setup_net+0x400/0x740 net/core/net_namespace.c:333 copy_net_ns+0x1df/0x340 net/core/net_namespace.c:439 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:103 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:202 ksys_unshare+0x440/0x980 kernel/fork.c:2692 __do_sys_unshare kernel/fork.c:2760 [inline] __se_sys_unshare kernel/fork.c:2758 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2758 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4592c9 Code: ff ff ff 48 8b 49 30 48 89 4c 24 10 48 8b 50 08 48 89 91 20 01 00 00 48 8d 50 08 84 02 48 89 ca 48 89 50 08 48 89 04 24 e8 34 <63> fb ff 48 8b 44 24 10 48 8d 88 10 01 00 00 48 89 4c 24 18 48 89 RSP: 002b:00007f53e0877c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00000000004592c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f53e08786d4 R13: 00000000004c87c1 R14: 00000000004df260 R15: 00000000ffffffff INFO: task syz-executor.2:23583 blocked for more than 143 seconds. Not tainted 5.2.0-rc5+ #56 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D25664 23583 8677 0x80004004 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3568 __mutex_lock_common kernel/locking/mutex.c:1003 [inline] __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1073 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 cangw_pernet_exit+0x13/0x30 net/can/gw.c:1029 ops_exit_list.isra.0+0xaa/0x150 net/core/net_namespace.c:154 setup_net+0x400/0x740 net/core/net_namespace.c:333 copy_net_ns+0x1df/0x340 net/core/net_namespace.c:439 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:103 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:202 ksys_unshare+0x440/0x980 kernel/fork.c:2692 __do_sys_unshare kernel/fork.c:2760 [inline] __se_sys_unshare kernel/fork.c:2758 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2758 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4592c9 Code: ff ff ff 48 8b 49 30 48 89 4c 24 10 48 8b 50 08 48 89 91 20 01 00 00 48 8d 50 08 84 02 48 89 ca 48 89 50 08 48 89 04 24 e8 34 <63> fb ff 48 8b 44 24 10 48 8d 88 10 01 00 00 48 89 4c 24 18 48 89 RSP: 002b:00007f4b263a2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00000000004592c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4b263a36d4 R13: 00000000004c87c1 R14: 00000000004df260 R15: 00000000ffffffff Showing all locks held in the system: 4 locks held by kworker/u4:1/21: #0: 000000009b53fe28 ((wq_completion)netns){+.+.}, at: __write_once_size include/linux/compiler.h:221 [inline] #0: 000000009b53fe28 ((wq_completion)netns){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000009b53fe28 ((wq_completion)netns){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 000000009b53fe28 ((wq_completion)netns){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 000000009b53fe28 ((wq_completion)netns){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: 000000009b53fe28 ((wq_completion)netns){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: 000000009b53fe28 ((wq_completion)netns){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240 #1: 0000000018fab4fb (net_cleanup_work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244 #2: 000000007a3172e3 (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0x960 net/core/net_namespace.c:520 #3: 00000000c9da4430 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by khungtaskd/1043: #0: 0000000083dd9689 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5149 2 locks held by rsyslogd/8537: #0: 00000000005436db (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 #1: 000000006b673a91 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1168 [inline] #1: 000000006b673a91 (&rq->lock){-.-.}, at: __schedule+0x1f5/0x1560 kernel/sched/core.c:3397 2 locks held by getty/8627: #0: 0000000022d0b05a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000053dd6528 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8628: #0: 0000000051ec0d55 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000017c81222 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8629: #0: 00000000133f6809 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e8a8dafe (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8630: #0: 0000000051c6795a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000094ab9990 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8631: #0: 00000000b7814c08 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000077a1bdb1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8632: #0: 0000000089152a59 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000002bc007ea (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8633: #0: 00000000e64340b8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000005a0eb668 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 3 locks held by kworker/1:22/16634: #0: 000000007c751bc3 ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size include/linux/compiler.h:221 [inline] #0: 000000007c751bc3 ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 000000007c751bc3 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 000000007c751bc3 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 000000007c751bc3 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: 000000007c751bc3 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: 000000007c751bc3 ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x87e/0x1790 kernel/workqueue.c:2240 #1: 000000000d4c503d ((addr_chk_work).work){+.+.}, at: process_one_work+0x8b4/0x1790 kernel/workqueue.c:2244 #2: 00000000c9da4430 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 2 locks held by syz-executor.5/23578: #0: 000000007a3172e3 (pernet_ops_rwsem){++++}, at: copy_net_ns+0x1c0/0x340 net/core/net_namespace.c:435 #1: 00000000c9da4430 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 2 locks held by syz-executor.2/23583: #0: 000000007a3172e3 (pernet_ops_rwsem){++++}, at: copy_net_ns+0x1c0/0x340 net/core/net_namespace.c:435 #1: 00000000c9da4430 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1043 Comm: khungtaskd Not tainted 5.2.0-rc5+ #56 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:205 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:289 kthread+0x354/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 45 Comm: kworker/u4:2 Not tainted 5.2.0-rc5+ #56 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:debug_smp_processor_id+0x0/0x280 lib/smp_processor_id.c:56 Code: e9 41 ff ff ff e8 90 e2 73 fe eb a2 4c 89 f7 e8 a6 e2 73 fe e9 a4 fe ff ff e8 9c e2 73 fe e9 78 fe ff ff 0f 1f 80 00 00 00 00 <55> 48 89 e5 41 56 41 55 41 54 53 e8 f0 35 3b fe 65 44 8b 25 e8 05 RSP: 0018:ffff8880a9ae7ca0 EFLAGS: 00000292 RAX: ffff8880a9af4440 RBX: 00000000000362c0 RCX: ffffffff8700f1e1 RDX: 0000000000000000 RSI: ffffffff8700f470 RDI: 0000000000000001 RBP: ffff8880a9ae7cc0 R08: ffff8880a9af4440 R09: ffffed1015d06c70 R10: ffffed1015d06c6f R11: ffff8880ae83637b R12: 0000000000000001 R13: 0000000000000348 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c4269ab010 CR3: 00000000a7de8000 CR4: 00000000001406f0 DR0: 0000000061efe74d DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_is_watching+0x10/0x30 kernel/rcu/tree.c:872 rcu_read_unlock include/linux/rcupdate.h:643 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:411 [inline] batadv_nc_worker+0x485/0x760 net/batman-adv/network-coding.c:718 process_one_work+0x989/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x354/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352