INFO: task syz-executor.0:24217 blocked for more than 143 seconds. Not tainted 5.3.0-rc8+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28160 24217 9087 0x00000004 Call Trace: context_switch kernel/sched/core.c:3254 [inline] __schedule+0x755/0x1580 kernel/sched/core.c:3880 schedule+0xd9/0x260 kernel/sched/core.c:3947 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:9319 packet_release+0x9cf/0xcb0 net/packet/af_packet.c:3040 __sock_release+0xce/0x280 net/socket.c:590 sock_close+0x1e/0x30 net/socket.c:1268 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x5a9/0x6a0 arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4135d1 Code: 49 89 c9 48 85 d2 0f 84 e3 02 00 00 44 0f b6 32 48 ff c2 b9 08 00 00 00 49 39 f5 0f 85 9c 02 00 00 48 8b 73 08 48 c1 ee 03 48 <85> f6 0f 84 fc 03 00 00 48 83 fe 02 0f 83 79 02 00 00 bb 02 00 00 RSP: 002b:00007ffde27a13f0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00000000004135d1 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 0000000000000001 R08: 000000004a340ddd R09: 000000004a340de1 R10: 00007ffde27a14d0 R11: 0000000000000293 R12: 000000000075bf20 R13: 0000000000073f66 R14: 0000000000760320 R15: 000000000075bf2c Showing all locks held in the system: 2 locks held by kworker/u4:1/21: #0: 00000000166a4f0b (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:9874 [inline] #0: 00000000166a4f0b (&rq->lock){-.-.}, at: pick_next_task_fair+0xc42/0x1a60 kernel/sched/fair.c:6911 #1: 0000000034804a6f (rcu_read_lock){....}, at: __update_idle_core+0x45/0x3f0 kernel/sched/fair.c:5879 1 lock held by khungtaskd/1057: #0: 0000000034804a6f (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5256 1 lock held by rsyslogd/8958: #0: 00000000c36674e2 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9048: #0: 000000004d1705e3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: 000000002d98436b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9049: #0: 000000000da15ccb (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: 000000000da4a5a5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9050: #0: 00000000ac0b3c9d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: 00000000aa68fe21 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9051: #0: 000000002b097dae (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: 000000005b8a77e5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9052: #0: 000000002b7c55de (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: 000000008fba1b16 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9053: #0: 00000000e99dc897 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: 000000003e7aa0d9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/9054: #0: 00000000da583278 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: 00000000c332b2a4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.0/24217: #0: 00000000f7fd357e (&sb->s_type->i_mutex_key#12){+.+.}, at: inode_lock include/linux/fs.h:778 [inline] #0: 00000000f7fd357e (&sb->s_type->i_mutex_key#12){+.+.}, at: __sock_release+0x89/0x280 net/socket.c:589 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1057 Comm: khungtaskd Not tainted 5.3.0-rc8+ #0 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 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60