INFO: task syz-executor.3:17905 blocked for more than 143 seconds. Not tainted 5.1.0-rc6+ #164 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28384 17905 7788 0x00000004 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 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:582 [inline] rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:611 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 unregister_netdevice_notifier+0x7e/0x3a0 net/core/dev.c:1717 raw_release+0x57/0x6f0 net/can/raw.c:358 __sock_release+0xd3/0x2b0 net/socket.c:599 sock_close+0x1b/0x30 net/socket.c:1267 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x412b61 Code: 24 00 8b 93 04 01 00 00 85 d2 89 54 24 0c 0f 8e 2f 02 00 00 4c 8b 7c 24 28 c7 44 24 20 00 00 00 00 41 bd ff ff ff ff 45 31 f6 40 0f 1f 44 00 00 48 8b 75 00 48 85 f6 74 3a 48 8b 7c 24 10 e8 RSP: 002b:00007ffef85166e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000412b61 RDX: 0000000000000000 RSI: 000000000000019c RDI: 0000000000000004 RBP: 0000000000000001 R08: 00000000da61619c R09: 00000000da6161a0 R10: 00007ffef85167c0 R11: 0000000000000293 R12: 000000000073c900 R13: 000000000073c900 R14: 000000000016cd4a R15: 000000000073bfac Showing all locks held in the system: 1 lock held by khungtaskd/1041: #0: 000000008b83e281 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5057 4 locks held by kworker/u4:5/3041: 1 lock held by rsyslogd/7652: #0: 00000000d19a9e66 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/7743: #0: 0000000093f8c61a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000dfc09f51 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7744: #0: 000000005f0c8f3c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000fbac2c2a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7745: #0: 0000000095767f55 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000004c094394 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7746: #0: 0000000080946776 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000000a01160d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7747: #0: 00000000d75f9cc7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e03256a8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7748: #0: 00000000150910e3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000bf876c07 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/7749: #0: 00000000eac80243 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000d3a0f0d1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.3/17905: #0: 00000000f59a310c (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:772 [inline] #0: 00000000f59a310c (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2b0 net/socket.c:598 #1: 0000000090f64ab6 (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x7e/0x3a0 net/core/dev.c:1717 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1041 Comm: khungtaskd Not tainted 5.1.0-rc6+ #164 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 0 to CPUs 1: