INFO: task syz-executor.2:26519 blocked for more than 140 seconds. Not tainted 4.19.55 #27 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29496 26519 7977 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:00007f2e21840c78 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: 00007f2e218416d4 R13: 00000000004c7ceb R14: 00000000004de1e0 R15: 00000000ffffffff Showing all locks held in the system: kobject: 'wlan1683' (000000004338bf88): kobject_cleanup, parent (null) 1 lock held by khungtaskd/1035: #0: 000000007ffe374f (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4435 1 lock held by rsyslogd/7806: kobject: 'wlan1683' (000000004338bf88): calling ktype release #0: 00000000e6213666 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 kobject: 'wlan1683': free name 2 locks held by getty/7928: #0: 0000000005c2c340 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 000000000e654211 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 kobject: 'rfkill1700' (0000000076f5558b): kobject_uevent_env 2 locks held by getty/7929: kobject: 'rfkill1700' (0000000076f5558b): fill_kobj_path: path = '/devices/virtual/mac80211_hwsim/hwsim1724/ieee80211/phy1723/rfkill1700' #0: 00000000cf157da5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 000000005bb98f20 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7930: #0: 00000000ab850127 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000ec84ee31 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7931: #0: 00000000fa966809 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000984b5fe3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7932: #0: 000000003d6e67fd (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000cddf94b7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7933: #0: 00000000409f6349 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 0000000022245371 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7934: #0: 000000004caea03e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:363 #1: 00000000941d1d60 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 4 locks held by kworker/u4:3/10950: #0: 00000000b4fc1647 ((wq_completion)"%s""netns"){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline] #0: 00000000b4fc1647 ((wq_completion)"%s""netns"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: 00000000b4fc1647 ((wq_completion)"%s""netns"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline] #0: 00000000b4fc1647 ((wq_completion)"%s""netns"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline] #0: 00000000b4fc1647 ((wq_completion)"%s""netns"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline] #0: 00000000b4fc1647 ((wq_completion)"%s""netns"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: 00000000b4fc1647 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124 #1: 0000000049950582 (net_cleanup_work){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128 #2: 0000000072768b20 (pernet_ops_rwsem){++++}, at: cleanup_net+0xae/0x960 net/core/net_namespace.c:519 #3: 00000000647de6fe (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77 1 lock held by syz-executor.2/26519: #0: 0000000072768b20 (pernet_ops_rwsem){++++}, at: register_netdevice_notifier+0x7e/0x630 net/core/dev.c:1642 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1035 Comm: khungtaskd Not tainted 4.19.55 #27 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3460 Comm: kworker/u4:4 Not tainted 4.19.55 #27 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:677 [inline] RIP: 0010:batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:423 [inline] RIP: 0010:batadv_nc_worker+0x47b/0x760 net/batman-adv/network-coding.c:730 Code: 00 00 48 8b 35 26 67 1b 04 4c 89 e2 b9 01 00 00 00 bf 40 00 00 00 e8 54 ca 71 fa 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 f0 77 96 fa e8 9b d3 84 fa 31 ff 41 89 c6 89 c6 e8 1f 79 96 fa RSP: 0018:ffff888212067ce0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880a4d7c500 RCX: ffffffff86d49c31 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff888212067d30 R08: ffff888039952600 R09: ffffed1015d04733 R10: ffffed1015d04732 R11: ffff8880ae823993 R12: 0000000000000001 R13: 0000000000000184 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 0000000097158000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: process_one_work+0x989/0x1750 kernel/workqueue.c:2153 worker_thread+0x98/0xe40 kernel/workqueue.c:2296 kthread+0x354/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415