INFO: task syz-executor.4:9725 blocked for more than 143 seconds. Not tainted 5.2.0-rc1+ #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28128 9725 8882 0x00000004 Call Trace: context_switch kernel/sched/core.c:2817 [inline] __schedule+0x7cb/0x1560 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+0xce/0x2a0 net/socket.c:607 sock_close+0x1b/0x30 net/socket.c:1279 __fput+0x2ff/0x890 fs/file_table.c:279 ____fput+0x16/0x20 fs/file_table.c:312 task_work_run+0x145/0x1c0 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+0x58e/0x680 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x412f61 Code: 84 3e 02 00 00 48 8b 08 48 8b 54 24 70 48 39 d1 0f 85 41 01 00 00 0f b6 48 17 f6 c1 40 0f 85 99 00 00 00 0f b6 0d 23 ef 39 01 <84> c9 0f 84 80 00 00 00 48 8b 48 20 31 d2 31 db eb 04 48 83 c2 08 RSP: 002b:00007ffda2ece6a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000008 RCX: 0000000000412f61 RDX: 0000000000000000 RSI: ffffffff871c5a52 RDI: 0000000000000007 RBP: 0000000000000001 R08: ffffffff8132b13a R09: 00000000bfb24202 R10: 00007ffda2ece780 R11: 0000000000000293 R12: 000000000075c920 R13: 000000000075c920 R14: 00000000000297d8 R15: 000000000075c06c Showing all locks held in the system: 1 lock held by khungtaskd/1041: #0: 00000000acbd2997 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5148 2 locks held by rsyslogd/8739: #0: 00000000a8b43464 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 #1: 000000001f8b97e1 (logbuf_lock){-.-.}, at: __might_fault+0xfb/0x1e0 mm/memory.c:4494 2 locks held by getty/8829: #0: 000000007cedcef1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000e4f398e9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8830: #0: 000000005101971d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000b769aa9c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8831: #0: 00000000386cbcb3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000005ac11477 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8832: #0: 00000000e32f7e03 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000cfc427c4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8833: #0: 000000003804f270 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000000a4bec15 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8834: #0: 0000000030e54a43 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000d10ed247 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/8835: #0: 000000006b58f932 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000083268872 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.4/9725: #0: 000000007dee1ad5 (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:778 [inline] #0: 000000007dee1ad5 (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2a0 net/socket.c:606 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1041 Comm: khungtaskd Not tainted 5.2.0-rc1+ #3 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+0x354/0x420 kernel/kthread.c:254 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 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