INFO: task udevd:4186 blocked for more than 143 seconds. Not tainted 5.15.173-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:22624 pid: 4186 ppid: 3545 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515 __mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 device_lock include/linux/device.h:760 [inline] uevent_show+0x17e/0x340 drivers/base/core.c:2408 dev_attr_show+0x50/0xb0 drivers/base/core.c:2110 sysfs_kf_seq_show+0x313/0x4e0 fs/sysfs/file.c:61 seq_read_iter+0x43a/0xd10 fs/seq_file.c:230 call_read_iter include/linux/fs.h:2168 [inline] new_sync_read fs/read_write.c:404 [inline] vfs_read+0xa93/0xe10 fs/read_write.c:485 ksys_read+0x1a2/0x2c0 fs/read_write.c:623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f1167940b6a RSP: 002b:00007fff6541a458 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000056144a7c9f30 RCX: 00007f1167940b6a RDX: 0000000000001000 RSI: 000056144a7b0690 RDI: 0000000000000008 RBP: 000056144a7c9f30 R08: 0000000000000008 R09: 0000000000000004 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007fff6541a938 R15: 000000000000000a Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8cb1fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3924: #0: ffff88814d159098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cd62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 4 locks held by udevd/4186: #0: ffff888073357418 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xae/0xd10 fs/seq_file.c:182 #1: ffff88802489fc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x50/0x3b0 fs/kernfs/file.c:112 #2: ffff888025fdb490 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x3b0 fs/kernfs/file.c:113 #3: ffff888074bed1a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #3: ffff888074bed1a8 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17e/0x340 drivers/base/core.c:2408 2 locks held by kworker/1:6/4217: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0} , at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000313fd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/u4:6/4231: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000318fd20 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 3 locks held by kworker/0:18/6217: #0: ffff888141bb9938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900038cfd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffff88802410f220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #2: ffff88802410f220 (&dev->mutex){....}-{3:3}, at: hub_event+0x208/0x54c0 drivers/usb/core/hub.c:5769 2 locks held by kworker/0:20/6219: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000397fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 2 locks held by kworker/1:15/7482: #0: ffff888017471938 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900031ffd20 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 9 locks held by kworker/1:20/7491: 1 lock held by syz-executor/14561: #0: ffffffff8cb24228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #0: ffffffff8cb24228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 2 locks held by syz.5.1916/16672: #0: ffff88807a9400e0 (&type->s_umount_key#62/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229 #1: ffffffff8cb24228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #1: ffffffff8cb24228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 1 lock held by dhcpcd/16793: #0: ffff888064482120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff888064482120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 1 lock held by dhcpcd/16794: #0: ffff88805fbd0120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff88805fbd0120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 1 lock held by dhcpcd/16795: #0: ffff888074fb7410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline] #0: ffff888074fb7410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline] #0: ffff888074fb7410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x98/0x230 net/socket.c:1336 1 lock held by dhcpcd/16796: #0: ffff888053dc2120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff888053dc2120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 1 lock held by dhcpcd/16797: #0: ffff88807aba2120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1678 [inline] #0: ffff88807aba2120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xd50 net/packet/af_packet.c:3227 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.173-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xe72/0xeb0 kernel/hung_task.c:295 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:108 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562