INFO: task syz-executor.4:31707 blocked for more than 140 seconds. Not tainted 4.19.50 #22 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29192 31707 7697 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x80d/0x1c70 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:618 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+0x53/0x90 kernel/locking/rwsem.c:72 register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1642 bcm_init+0x1a8/0x220 net/can/bcm.c:1502 can_create+0x288/0x4a0 net/can/af_can.c:183 __sock_create+0x3d8/0x730 net/socket.c:1276 sock_create net/socket.c:1316 [inline] __sys_socket+0x103/0x220 net/socket.c:1346 __do_sys_socket net/socket.c:1355 [inline] __se_sys_socket net/socket.c:1353 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1353 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4592c9 Code: Bad RIP value. RSP: 002b:00007f719b354c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004592c9 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f719b3556d4 R13: 00000000004c7ceb R14: 00000000004de1e0 R15: 00000000ffffffff INFO: task syz-executor.4:31708 blocked for more than 140 seconds. Not tainted 4.19.50 #22 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29496 31708 7697 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x80d/0x1c70 kernel/sched/core.c:3474 schedule+0x92/0x1c0 kernel/sched/core.c:3518 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:618 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+0x53/0x90 kernel/locking/rwsem.c:72 register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1642 bcm_init+0x1a8/0x220 net/can/bcm.c:1502 can_create+0x288/0x4a0 net/can/af_can.c:183 __sock_create+0x3d8/0x730 net/socket.c:1276 sock_create net/socket.c:1316 [inline] __sys_socket+0x103/0x220 net/socket.c:1346 __do_sys_socket net/socket.c:1355 [inline] __se_sys_socket net/socket.c:1353 [inline] __x64_sys_socket+0x73/0xb0 net/socket.c:1353 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4592c9 Code: d3 ee 40 80 ff f8 77 05 48 8b 3f eb 08 48 8b 7c 1f f8 48 d3 ef 48 29 f7 48 d3 e7 0f 94 00 c3 cc cc 48 8b 74 24 08 48 8b 5c 24 <10> 48 8b 7c 24 18 48 8b 54 24 20 4c 8d 4c 24 28 e9 02 00 00 00 cc RSP: 002b:00007f719b333c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004592c9 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f719b3346d4 R13: 00000000004c7ceb R14: 00000000004de1e0 R15: 00000000ffffffff Showing all locks held in the system: 3 locks held by kworker/u4:2/34: 1 lock held by khungtaskd/1030: #0: 00000000b349b9d3 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4435 3 locks held by rs:main Q:Reg/7521: 1 lock held by rsyslogd/7524: #0: 00000000c3a782bc (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 2 locks held by getty/7646: #0: 000000005bd62421 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 0000000009e993ed (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7647: #0: 00000000bd7fb107 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000f6fe6fa2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7648: #0: 00000000191e96de (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000c6db1409 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7649: #0: 0000000062bfe056 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 000000003bc5b771 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7650: #0: 00000000144f07c4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 000000002871a6ae (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7651: #0: 00000000d58476c4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 000000006ded91e5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7652: #0: 000000007c8b1692 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 0000000003d27ff4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by kworker/u4:3/8529: #0: 000000001b9dbab1 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1821 [inline] #0: 000000001b9dbab1 (&rq->lock){-.-.}, at: __schedule+0x1f8/0x1c70 kernel/sched/core.c:3412 #1: 00000000b349b9d3 (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:423 [inline] #1: 00000000b349b9d3 (rcu_read_lock){....}, at: update_curr+0x2ce/0x8a0 kernel/sched/fair.c:828 1 lock held by syz-executor.4/31707: #0: 000000003a564691 (pernet_ops_rwsem){++++}, at: register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1642 1 lock held by syz-executor.4/31708: #0: 000000003a564691 (pernet_ops_rwsem){++++}, at: register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1642 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1030 Comm: khungtaskd Not tainted 4.19.50 #22 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+0x1b0/0x1f8 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:203 [inline] watchdog+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7521 Comm: rs:main Q:Reg Not tainted 4.19.50 #22 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0033:0x4322c0 Code: 40 fc ff ff 41 8b 6f 2c 31 db 85 ed 0f 8e c9 fd ff ff 83 c3 01 4c 89 ef 41 ff 95 d0 00 00 00 39 eb 75 ef e9 b3 fd ff ff 66 90 <48> 89 5c 24 e0 48 89 6c 24 e8 48 89 fd 4c 89 64 24 f0 4c 89 6c 24 RSP: 002b:00007f14d7b07cd8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000001caa8b0 RSI: 0000000001caaa10 RDI: 0000000001cbb120 RBP: 0000000000000000 R08: 0000000001cbab80 R09: 0000000000001d61 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000447f18 R13: 000000000044421f R14: 0000000000447ee8 R15: 0000000000000003 FS: 00007f14d7b08700 GS: 0000000000000000