INFO: task syz-executor.3:26631 blocked for more than 143 seconds. Not tainted 5.1.0+ #9 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28128 26631 13520 0x00000004 Call Trace: context_switch kernel/sched/core.c:2817 [inline] __schedule+0x7d1/0x1580 kernel/sched/core.c:3444 schedule+0xa8/0x260 kernel/sched/core.c:3508 exp_funnel_lock kernel/rcu/tree_exp.h:309 [inline] synchronize_rcu_expedited+0x54e/0x5b0 kernel/rcu/tree_exp.h:790 synchronize_net+0x3b/0x60 net/core/dev.c:9279 packet_release+0x806/0xbf0 net/packet/af_packet.c:3015 __sock_release+0xd3/0x2b0 net/socket.c:607 sock_close+0x1b/0x30 net/socket.c:1279 __fput+0x302/0x890 fs/file_table.c:279 ____fput+0x16/0x20 fs/file_table.c:312 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:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x594/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x412b61 Code: 01 00 00 64 48 8b 04 25 f8 ff ff ff 48 8b 40 30 48 8b 80 98 00 00 00 48 85 c0 74 15 48 8b 08 48 39 d1 77 0d 48 8b 40 08 48 39 0f 82 fb 00 00 00 48 8b 05 f1 45 37 01 48 85 c0 0f 84 e2 00 00 RSP: 002b:00007ffd8c3985a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000412b61 RDX: 0000001b30820000 RSI: ffffffff871b63a4 RDI: 0000000000000003 RBP: 0000000000000001 R08: ffffffff8100a004 R09: 00000000bb5eab85 R10: 00007ffd8c398680 R11: 0000000000000293 R12: 000000000073c900 R13: 000000000073c900 R14: 000000000010aaea R15: 000000000073bfac INFO: task syz-executor.1:26646 blocked for more than 143 seconds. Not tainted 5.1.0+ #9 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D27296 26646 26129 0x00000004 Call Trace: context_switch kernel/sched/core.c:2817 [inline] __schedule+0x7d1/0x1580 kernel/sched/core.c:3444 schedule+0xa8/0x260 kernel/sched/core.c:3508 exp_funnel_lock kernel/rcu/tree_exp.h:309 [inline] synchronize_rcu_expedited+0x54e/0x5b0 kernel/rcu/tree_exp.h:790 synchronize_net+0x3b/0x60 net/core/dev.c:9279 packet_release+0x806/0xbf0 net/packet/af_packet.c:3015 __sock_release+0xd3/0x2b0 net/socket.c:607 sock_close+0x1b/0x30 net/socket.c:1279 __fput+0x302/0x890 fs/file_table.c:279 ____fput+0x16/0x20 fs/file_table.c:312 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:168 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x594/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x412b61 Code: 01 00 00 64 48 8b 04 25 f8 ff ff ff 48 8b 40 30 48 8b 80 98 00 00 00 48 85 c0 74 15 48 8b 08 48 39 d1 77 0d 48 8b 40 08 48 39 0f 82 fb 00 00 00 48 8b 05 f1 45 37 01 48 85 c0 0f 84 e2 00 00 RSP: 002b:00007fff76552b00 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000412b61 RDX: 0000001b2cb20000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: ffffffff8132c3f2 R09: 000000001b156385 R10: 00007fff76552be0 R11: 0000000000000293 R12: 000000000073c900 R13: 000000000073c900 R14: 000000000010abc0 R15: 000000000073c04c Showing all locks held in the system: 1 lock held by khungtaskd/1041: #0: 0000000050d36108 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5148 2 locks held by kworker/u4:4/2547: #0: 0000000065064846 (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:10083 [inline] #0: 0000000065064846 (&rq->lock){-.-.}, at: pick_next_task_fair+0x1214/0x19a0 kernel/sched/fair.c:7090 #1: 0000000050d36108 (rcu_read_lock){....}, at: __update_idle_core+0x45/0x3f0 kernel/sched/fair.c:6087 1 lock held by rsyslogd/9033: #0: 0000000022b3c973 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9123: #0: 000000002eb38a68 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000ca4a4c1e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9124: #0: 000000006be115c4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000078bafa1c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9125: #0: 00000000aebd3861 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000175d0ee6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9126: #0: 0000000026720c54 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000093b15b72 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9127: #0: 00000000050dee79 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000eced6ce2 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9128: #0: 00000000d97e091d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000090690c87 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9129: #0: 000000002f5fcade (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000009050b420 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.3/26631: #0: 00000000ba9f1b1d (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:778 [inline] #0: 00000000ba9f1b1d (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2b0 net/socket.c:606 1 lock held by syz-executor.1/26646: #0: 000000009b9e6e16 (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:778 [inline] #0: 000000009b9e6e16 (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2b0 net/socket.c:606 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1041 Comm: khungtaskd Not tainted 5.1.0+ #9 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: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60