INFO: task kworker/u4:7:5277 blocked for more than 143 seconds. Not tainted 6.3.0-rc2-syzkaller-00050-g9c1bec9c0b08 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:7 state:D stack:27296 pid:5277 ppid:2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:5304 [inline] __schedule+0xc91/0x5770 kernel/sched/core.c:6622 schedule+0xde/0x1a0 kernel/sched/core.c:6698 schedule_timeout+0x276/0x2b0 kernel/time/timer.c:2143 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common+0x1ce/0x5c0 kernel/sched/completion.c:106 io_ring_exit_work+0x521/0x1370 io_uring/io_uring.c:3027 process_one_work+0x991/0x15c0 kernel/workqueue.c:2390 worker_thread+0x669/0x1090 kernel/workqueue.c:2537 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Showing all locks held in the system: 2 locks held by kworker/u4:0/9: #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x87a/0x15c0 kernel/workqueue.c:2361 #1: ffffc900000e7da8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x15c0 kernel/workqueue.c:2365 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8c794b70 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:510 1 lock held by rcu_tasks_trace/13: #0: ffffffff8c794870 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:510 2 locks held by kworker/0:1/14: #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x87a/0x15c0 kernel/workqueue.c:2361 #1: ffffc90000137da8 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x15c0 kernel/workqueue.c:2365 5 locks held by kworker/1:0/22: #0: ffff888017e14138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888017e14138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888017e14138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888017e14138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff888017e14138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff888017e14138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x87a/0x15c0 kernel/workqueue.c:2361 #1: ffffc900001c7da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x15c0 kernel/workqueue.c:2365 #2: ffff88802159e190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:832 [inline] #2: ffff88802159e190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c0/0x4e40 drivers/usb/core/hub.c:5739 #3: ffff88802ca03190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:832 [inline] #3: ffff88802ca03190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x76/0x4b0 drivers/base/dd.c:973 #4: ffff88807d7ab118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:832 [inline] #4: ffff88807d7ab118 (&dev->mutex){....}-{3:3}, at: __device_attach+0x76/0x4b0 drivers/base/dd.c:973 1 lock held by khungtaskd/28: #0: ffffffff8c7956c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x340 kernel/locking/lockdep.c:6495 2 locks held by kworker/u4:2/33: 2 locks held by getty/4758: #0: ffff888027f5b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc900015902f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef4/0x13e0 drivers/tty/n_tty.c:2177 3 locks held by kworker/1:4/5175: #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x87a/0x15c0 kernel/workqueue.c:2361 #1: ffffc90004697da8 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x15c0 kernel/workqueue.c:2365 #2: ffffffff8e0fc648 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xa7/0x1390 net/ipv6/addrconf.c:4088 3 locks held by kworker/0:4/5177: #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff8881477d0538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x87a/0x15c0 kernel/workqueue.c:2361 #1: ffffc900047d7da8 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x15c0 kernel/workqueue.c:2365 #2: ffffffff8e0fc648 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xa7/0x1390 net/ipv6/addrconf.c:4088 2 locks held by kworker/u4:7/5277: #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x87a/0x15c0 kernel/workqueue.c:2361 #1: ffffc90004a2fda8 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x15c0 kernel/workqueue.c:2365 1 lock held by syz-executor.0/5356: 1 lock held by syz-executor.2/5446: 1 lock held by syz-executor.5/5455: 1 lock held by syz-executor.1/5486: 1 lock held by syz-executor.0/5512: 3 locks held by syz-executor.0/5626: #0: ffffffff8e0fc648 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:75 [inline] #0: ffffffff8e0fc648 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3e8/0xd50 net/core/rtnetlink.c:6171 #1: ffff8880242113e8 (&wg->device_update_lock){+.+.}-{3:3}, at: wg_open+0x1f5/0x4d0 drivers/net/wireguard/device.c:49 #2: ffffffff8c7a09b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:293 [inline] #2: ffffffff8c7a09b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x64a/0x770 kernel/rcu/tree_exp.h:989 1 lock held by syz-executor.3/5656: 1 lock held by syz-executor.3/5658: #0: ffff8880755340a8 (&ctx->uring_lock){+.+.}-{3:3}, at: __do_sys_io_uring_register+0x19c/0x2400 io_uring/io_uring.c:4342 1 lock held by syz-executor.1/5673: 1 lock held by syz-executor.1/5679: #0: ffff88805065e0a8 (&ctx->uring_lock){+.+.}-{3:3}, at: __do_sys_io_uring_register+0x19c/0x2400 io_uring/io_uring.c:4342 1 lock held by syz-executor.1/5680: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.3.0-rc2-syzkaller-00050-g9c1bec9c0b08 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 nmi_cpu_backtrace+0x29c/0x350 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x2a4/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xe16/0x1090 kernel/hung_task.c:379 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x40/0x50 drivers/acpi/processor_idle.c:112