INFO: task syz-executor.0:31827 blocked for more than 140 seconds. Not tainted 5.0.0+ #97 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29024 31827 7577 0x00000006 Call Trace: context_switch kernel/sched/core.c:2844 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3485 schedule+0x92/0x180 kernel/sched/core.c:3529 exp_funnel_lock kernel/rcu/tree_exp.h:319 [inline] _synchronize_rcu_expedited.constprop.0+0x4d4/0x530 kernel/rcu/tree_exp.h:622 synchronize_rcu_expedited+0x27/0xa0 kernel/rcu/tree_exp.h:762 synchronize_net+0x3b/0x60 net/core/dev.c:9247 packet_set_ring+0x23c/0x1b50 net/packet/af_packet.c:4342 packet_release+0x558/0xbf0 net/packet/af_packet.c:3001 __sock_release+0xd3/0x2b0 net/socket.c:579 sock_close+0x1b/0x30 net/socket.c:1162 __fput+0x2df/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 get_signal+0x1961/0x1d50 kernel/signal.c:2388 do_signal+0x87/0x1940 arch/x86/kernel/signal.c:816 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458079 Code: 0f b6 4a 28 48 8b 52 30 c6 81 c9 02 00 00 01 48 8b 4b 10 4c 8b 53 08 48 8b 1b 49 39 ca 0f 87 23 01 00 00 48 89 74 24 38 48 89 <7c> 24 30 4c 89 44 24 28 44 88 4c 24 27 48 89 54 24 50 48 89 44 24 RSP: 002b:00007ff40a8e7c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000458079 RDX: 0000000000000005 RSI: 0000000000000107 RDI: 0000000000000004 RBP: 000000000073bf00 R08: 000000000000001c R09: 0000000000000000 R10: 0000000020000040 R11: 0000000000000246 R12: 00007ff40a8e86d4 R13: 00000000004c614e R14: 00000000004db170 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1041: #0: 000000004add6bf9 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4389 1 lock held by rsyslogd/7450: 2 locks held by getty/7540: #0: 000000001360930c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000002ca7072e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7541: #0: 0000000012e09abd (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000009bf6447f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7542: #0: 000000009ae5ef8b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 00000000314363d1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7543: #0: 00000000deae7f66 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000008924362f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7544: #0: 00000000d9a41863 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 000000009eab6fb3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7545: #0: 00000000d09a2e62 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000001cff654 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by getty/7546: #0: 00000000e689041a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341 #1: 0000000026788a6c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2154 2 locks held by syz-executor.0/31827: #0: 00000000edd265db (&sb->s_type->i_mutex_key#11){+.+.}, at: inode_lock include/linux/fs.h:763 [inline] #0: 00000000edd265db (&sb->s_type->i_mutex_key#11){+.+.}, at: __sock_release+0x89/0x2b0 net/socket.c:578 #1: 00000000a2995e12 (sk_lock-AF_PACKET){+.+.}, at: lock_sock include/net/sock.h:1507 [inline] #1: 00000000a2995e12 (sk_lock-AF_PACKET){+.+.}, at: packet_release+0x4ff/0xbf0 net/packet/af_packet.c:2998 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1041 Comm: khungtaskd Not tainted 5.0.0+ #97 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:203 [inline] watchdog+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 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+0x2/0x10 arch/x86/include/asm/irqflags.h:57