INFO: task kworker/u4:3:475 blocked for more than 143 seconds. Not tainted 5.2.0+ #97 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:3 D24280 475 2 0x80004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:3254 [inline] __schedule+0x755/0x1580 kernel/sched/core.c:3880 schedule+0xa8/0x270 kernel/sched/core.c:3944 exp_funnel_lock kernel/rcu/tree_exp.h:308 [inline] synchronize_rcu_expedited+0x544/0x5b0 kernel/rcu/tree_exp.h:816 synchronize_net+0x3b/0x60 net/core/dev.c:9259 tipc_bcast_stop+0x198/0x310 net/tipc/bcast.c:705 tipc_exit_net+0x1e/0x40 net/tipc/core.c:98 ops_exit_list.isra.0+0xaa/0x150 net/core/net_namespace.c:172 cleanup_net+0x4e2/0xa70 net/core/net_namespace.c:594 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INFO: task syz-executor.5:18614 blocked for more than 143 seconds. Not tainted 5.2.0+ #97 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29712 18614 16620 0x00000004 Call Trace: context_switch kernel/sched/core.c:3254 [inline] __schedule+0x755/0x1580 kernel/sched/core.c:3880 schedule+0xa8/0x270 kernel/sched/core.c:3944 rwsem_down_write_slowpath+0x708/0xf60 kernel/locking/rwsem.c:1198 __down_write kernel/locking/rwsem.c:1349 [inline] down_write+0x13c/0x150 kernel/locking/rwsem.c:1485 register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1644 raw_init+0x299/0x340 net/can/raw.c:343 can_create+0x288/0x4b0 net/can/af_can.c:178 __sock_create+0x3d8/0x730 net/socket.c:1418 sock_create net/socket.c:1469 [inline] __sys_socket+0x103/0x220 net/socket.c:1511 __do_sys_socket net/socket.c:1520 [inline] __se_sys_socket net/socket.c:1518 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1518 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459829 Code: 24 60 48 8b 42 08 48 8b 4a 10 48 8b 5a 18 48 8b 72 20 48 8b 7a 28 48 8b 3f 4c 8b 42 30 48 8b 52 38 48 85 d2 76 62 48 89 44 24 <58> 4c 89 44 24 28 48 89 0c 24 48 89 5c 24 08 48 c7 44 24 10 00 00 RSP: 002b:00007f10cb25dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f10cb25e6d4 R13: 00000000004c843c R14: 00000000004deed0 R15: 00000000ffffffff INFO: task syz-executor.5:18619 blocked for more than 143 seconds. Not tainted 5.2.0+ #97 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29712 18619 16620 0x00000004 Call Trace: context_switch kernel/sched/core.c:3254 [inline] __schedule+0x755/0x1580 kernel/sched/core.c:3880 schedule+0xa8/0x270 kernel/sched/core.c:3944 rwsem_down_write_slowpath+0x708/0xf60 kernel/locking/rwsem.c:1198 __down_write kernel/locking/rwsem.c:1349 [inline] down_write+0x13c/0x150 kernel/locking/rwsem.c:1485 register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1644 raw_init+0x299/0x340 net/can/raw.c:343 can_create+0x288/0x4b0 net/can/af_can.c:178 __sock_create+0x3d8/0x730 net/socket.c:1418 sock_create net/socket.c:1469 [inline] __sys_socket+0x103/0x220 net/socket.c:1511 __do_sys_socket net/socket.c:1520 [inline] __se_sys_socket net/socket.c:1518 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1518 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459829 Code: 24 60 48 8b 42 08 48 8b 4a 10 48 8b 5a 18 48 8b 72 20 48 8b 7a 28 48 8b 3f 4c 8b 42 30 48 8b 52 38 48 85 d2 76 62 48 89 44 24 <58> 4c 89 44 24 28 48 89 0c 24 48 89 5c 24 08 48 c7 44 24 10 00 00 RSP: 002b:00007f10cb23cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 000000000000001d RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f10cb23d6d4 R13: 00000000004c843c R14: 00000000004deed0 R15: 00000000ffffffff Showing all locks held in the system: 3 locks held by kworker/u4:3/475: #0: 00000000aeaeb84c ((wq_completion)netns){+.+.}, at: __write_once_size include/linux/compiler.h:221 [inline] #0: 00000000aeaeb84c ((wq_completion)netns){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000aeaeb84c ((wq_completion)netns){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: 00000000aeaeb84c ((wq_completion)netns){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: 00000000aeaeb84c ((wq_completion)netns){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: 00000000aeaeb84c ((wq_completion)netns){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: 00000000aeaeb84c ((wq_completion)netns){+.+.}, at: process_one_work+0x88b/0x1740 kernel/workqueue.c:2240 #1: 00000000235a5edc (net_cleanup_work){+.+.}, at: process_one_work+0x8c1/0x1740 kernel/workqueue.c:2244 #2: 00000000d467d52b (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0xa70 net/core/net_namespace.c:556 1 lock held by khungtaskd/1053: #0: 00000000a28dfbfe (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5257 2 locks held by rsyslogd/9115: #0: 00000000886cc4ca (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 #1: 00000000d6ed4061 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1207 [inline] #1: 00000000d6ed4061 (&rq->lock){-.-.}, at: __schedule+0x1f5/0x1580 kernel/sched/core.c:3832 2 locks held by getty/9205: #0: 000000000e0e901f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000ff773338 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9206: #0: 00000000823f602e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000d14fc3a5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9207: #0: 000000000d8dc7de (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000dd7568be (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9208: #0: 00000000ac185997 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000d4325c97 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9209: #0: 00000000d2aea0ea (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000029c57de9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9210: #0: 0000000002540521 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000b69e0bfe (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9211: #0: 0000000049dbf4fc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000d2667154 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.5/18614: #0: 00000000d467d52b (pernet_ops_rwsem){++++}, at: register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1644 1 lock held by syz-executor.5/18619: #0: 00000000d467d52b (pernet_ops_rwsem){++++}, at: register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1644 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1053 Comm: khungtaskd Not tainted 5.2.0+ #97 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+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b 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+0x9d0/0xef0 kernel/hung_task.c:289 kthread+0x361/0x430 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: 2648 Comm: kworker/u4:4 Not tainted 5.2.0+ #97 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:cpu_max_bits_warn include/linux/cpumask.h:121 [inline] RIP: 0010:cpumask_check include/linux/cpumask.h:128 [inline] RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:344 [inline] RIP: 0010:trace_lock_acquire include/trace/events/lock.h:13 [inline] RIP: 0010:lock_acquire+0x128/0x410 kernel/locking/lockdep.c:4412 Code: 89 f8 83 e0 07 83 c0 03 38 c8 7c 08 84 c9 0f 85 61 02 00 00 c7 82 8c 08 00 00 01 00 00 00 0f 1f 44 00 00 65 8b 15 38 bd a8 7e <83> fa 3f 0f 87 29 02 00 00 89 d2 be 08 00 00 00 48 89 d0 48 89 55 RSP: 0018:ffff8880a1f27be8 EFLAGS: 00000046 RAX: 0000000000000007 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a1f18b0c RBP: ffff8880a1f27c30 R08: 0000000000000001 R09: 0000000000000000 R10: fffffbfff14a7755 R11: ffffffff8a53baaf R12: ffff88805c886e58 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c429d49010 CR3: 000000008f86f000 CR4: 00000000001406f0 Call Trace: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x33/0x50 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:343 [inline] batadv_nc_purge_paths+0xd8/0x370 net/batman-adv/network-coding.c:441 batadv_nc_worker+0x2cf/0x760 net/batman-adv/network-coding.c:721 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352