INFO: task syz-executor.1:22294 blocked for more than 143 seconds. Not tainted 5.2.0-rc3+ #21 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28976 22294 15737 0x00004006 Call Trace: context_switch kernel/sched/core.c:2818 [inline] __schedule+0x7cb/0x1560 kernel/sched/core.c:3445 schedule+0xa8/0x260 kernel/sched/core.c:3509 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:9269 packet_release+0x99b/0xc60 net/packet/af_packet.c:3009 __sock_release+0xce/0x2a0 net/socket.c:601 sock_close+0x1b/0x30 net/socket.c:1273 __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 get_signal+0x201b/0x24b0 kernel/signal.c:2434 do_signal+0x87/0x1900 arch/x86/kernel/signal.c:815 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:164 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: 0033:0x4592c9 Code: ff ff ff 48 8b 49 30 48 89 4c 24 10 48 8b 50 08 48 89 91 20 01 00 00 48 8d 50 08 84 02 48 89 ca 48 89 50 08 48 89 04 24 e8 34 <63> fb ff 48 8b 44 24 10 48 8d 88 10 01 00 00 48 89 4c 24 18 48 89 RSP: 002b:00007f0913053c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002f RAX: fffffffffffffe00 RBX: 0000000000000003 RCX: 00000000004592c9 RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000005 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f09130546d4 R13: 00000000004c6629 R14: 00000000004db3c0 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1043: #0: 000000006b08cf22 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5149 1 lock held by rsyslogd/8976: #0: 00000000f25e64ac (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/9066: #0: 00000000481ed1f8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000048d5944e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9067: #0: 000000001360de8a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000426d5356 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9068: #0: 00000000378163e2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000002b265c9d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9069: #0: 0000000031761384 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000006046f22d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9070: #0: 00000000992ba47a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000ea16a65d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9071: #0: 000000008889a166 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000005f868b90 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 2 locks held by getty/9072: #0: 0000000027a76256 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000fb48554e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.1/22294: #0: 00000000d9376e40 (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:778 [inline] #0: 00000000d9376e40 (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2a0 net/socket.c:600 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1043 Comm: khungtaskd Not tainted 5.2.0-rc3+ #21 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:205 [inline] watchdog+0x9b7/0xec0 kernel/hung_task.c:289 kthread+0x354/0x420 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