NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 INFO: task syz-executor.1:8466 blocked for more than 140 seconds. Not tainted 4.19.105-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28040 8466 7981 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 exp_funnel_lock kernel/rcu/tree_exp.h:320 [inline] _synchronize_rcu_expedited+0x6b6/0x7f0 kernel/rcu/tree_exp.h:667 synchronize_rcu_expedited kernel/rcu/tree_exp.h:795 [inline] synchronize_rcu_expedited+0x35/0xb0 kernel/rcu/tree_exp.h:784 synchronize_net+0x3b/0x60 net/core/dev.c:9249 packet_release+0xa20/0xc70 net/packet/af_packet.c:3045 __sock_release+0xce/0x2a0 net/socket.c:579 sock_close+0x1b/0x30 net/socket.c:1140 __fput+0x2dd/0x8b0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:193 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:167 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x53d/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x415fe1 Code: 24 08 e8 22 4a 01 00 0f 0b 48 89 04 24 e8 a7 aa 03 00 48 8b 44 24 10 48 89 44 24 70 48 8b 4c 24 08 48 89 4c 24 78 48 8b 94 24 <88> 00 00 00 48 89 14 24 e8 82 aa 03 00 48 8b 44 24 10 48 8b 4c 24 RSP: 002b:00007fff850eed50 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000415fe1 RDX: 0000000000000000 RSI: ffffffff87545db3 RDI: 0000000000000006 RBP: 0000000000000001 R08: ffffffff8131871a R09: 00000000774eb528 R10: 00007fff850eee30 R11: 0000000000000293 R12: 000000000076c920 R13: 000000000076c920 R14: 0000000000035c04 R15: 000000000076bfcc Showing all locks held in the system: 2 locks held by kworker/u4:3/195: #0: 000000008e4bf39e (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:9647 [inline] #0: 000000008e4bf39e (&rq->lock){-.-.}, at: pick_next_task_fair+0xfae/0x1580 kernel/sched/fair.c:6819 #1: 0000000064661cd7 (rcu_read_lock){....}, at: __update_idle_core+0x45/0x3f0 kernel/sched/fair.c:6036 1 lock held by khungtaskd/1080: #0: 0000000064661cd7 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438 1 lock held by rsyslogd/7810: #0: 00000000614a9ad8 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767 2 locks held by getty/7932: #0: 00000000737b54ef (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000096ce7d91 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7933: #0: 000000002deef15a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000009b669eeb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7934: #0: 000000003dc80960 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000dcef88e7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7935: #0: 0000000053c8b57a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000003314fc84 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7936: #0: 00000000d77873a4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000a143d5d8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7937: #0: 000000003484b263 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000003e3cabe7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7938: #0: 00000000175064ee (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000188cf742 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 1 lock held by syz-executor.1/8466: #0: 000000002216db88 (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:747 [inline] #0: 000000002216db88 (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2a0 net/socket.c:578 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1080 Comm: khungtaskd Not tainted 4.19.105-syzkaller #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+0x197/0x210 lib/dump_stack.c:118 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 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60