INFO: task kworker/0:1:10 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:1 state:D stack:20552 pid:10 tgid:10 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153 i2c_del_adapter+0x581/0x6e0 drivers/i2c/i2c-core-base.c:1817 dvb_usb_i2c_exit+0x64/0xb0 drivers/media/usb/dvb-usb/dvb-usb-i2c.c:46 dvb_usb_exit drivers/media/usb/dvb-usb/dvb-usb-init.c:144 [inline] dvb_usb_device_exit+0x1be/0x350 drivers/media/usb/dvb-usb/dvb-usb-init.c:338 cxusb_probe+0x603/0x700 drivers/media/usb/dvb-usb/cxusb.c:1663 usb_probe_interface+0x665/0xc30 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26a/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 usb_set_configuration+0x1a87/0x20e0 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250 usb_probe_device+0x1c1/0x390 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26a/0x9e0 drivers/base/dd.c:659 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3689 usb_new_device+0xa39/0x16f0 drivers/usb/core/hub.c:2694 hub_port_connect drivers/usb/core/hub.c:5566 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x2958/0x4a20 drivers/usb/core/hub.c:5952 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 5 locks held by kworker/0:1/10: #0: ffff888021a84948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888021a84948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc900000f7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc900000f7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff8881453c7198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #2: ffff8881453c7198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898 #3: ffff888075836198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #3: ffff888075836198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1006 #4: ffff88807d791160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline] #4: ffff88807d791160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1006 1 lock held by khungtaskd/31: #0: ffffffff8dd3aca0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8dd3aca0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8dd3aca0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:3/37: 2 locks held by kworker/u8:5/1014: #0: ffff88801e359948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801e359948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000397fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000397fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 3 locks held by kworker/u8:6/3486: #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000c187bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000c187bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8f0cc8c8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 2 locks held by getty/5601: #0: ffff888032ea90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/0:4/5932: #0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000451fbc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000451fbc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8f0cc8c8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 2 locks held by kworker/u8:10/6779: #0: ffff88801e359948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801e359948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9001cb97bc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9001cb97bc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 2 locks held by kworker/u8:12/6782: 2 locks held by syz.0.1117/10138: #0: ffffffff8f0cc8c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f0cc8c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f0cc8c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 #1: ffffffff8dd40738 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline] #1: ffffffff8dd40738 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957 1 lock held by syz.2.1119/10145: #0: ffffffff8f0cc8c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f0cc8c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6952 2 locks held by syz.2.1119/10146: #0: ffff88807cbb70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffff88807cbb7130 (&tty->atomic_write_lock){+.+.}-{4:4}, at: tty_write_lock drivers/tty/tty_io.c:939 [inline] #1: ffff88807cbb7130 (&tty->atomic_write_lock){+.+.}-{4:4}, at: iterate_tty_write drivers/tty/tty_io.c:958 [inline] #1: ffff88807cbb7130 (&tty->atomic_write_lock){+.+.}-{4:4}, at: file_tty_write+0x211/0xa20 drivers/tty/tty_io.c:1081 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 10138 Comm: syz.0.1117 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:__rcu_read_lock+0x39/0x60 kernel/rcu/tree_plugin.h:420 Code: 81 c3 44 04 00 00 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 18 ff 03 8b 03 3d 00 00 00 40 7d 07 <5b> c3 cc cc cc cc cc 90 0f 0b 90 eb f3 89 d9 80 e1 07 80 c1 03 38 RSP: 0018:ffffc90000a08368 EFLAGS: 00000283 RAX: 0000000000000002 RBX: ffff88802b83a244 RCX: dffffc0000000000 RDX: dffffc0000000000 RSI: ffffffff8916b762 RDI: ffffc90000a08448 RBP: dffffc0000000000 R08: ffffc90000a08510 R09: 0000000000000004 R10: ffffc90000a08498 R11: ffffffff81aaa470 R12: 1ffff92000141089 R13: ffffc90000a08480 R14: ffffc90000a08448 R15: ffffc90000a088a0 FS: 00007feaba1ac6c0(0000) GS:ffff88812647e000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000361030 CR3: 000000002f2c4000 CR4: 00000000003526f0 Call Trace: rcu_read_lock include/linux/rcupdate.h:839 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x9e/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4191 [inline] slab_alloc_node mm/slub.c:4240 [inline] kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4292 kmalloc_reserve+0xbd/0x290 net/core/skbuff.c:578 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:669 skb_copy+0x188/0x800 net/core/skbuff.c:2124 mac80211_hwsim_tx_frame_no_nl+0xcd3/0x11c0 drivers/net/wireless/virtual/mac80211_hwsim.c:1871 mac80211_hwsim_tx_frame+0x1b5/0x200 drivers/net/wireless/virtual/mac80211_hwsim.c:2222 mac80211_hwsim_beacon_tx+0x3f0/0x860 drivers/net/wireless/virtual/mac80211_hwsim.c:2323 __iterate_interfaces+0x2a8/0x590 net/mac80211/util.c:761 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:797 mac80211_hwsim_beacon+0xbb/0x1c0 drivers/net/wireless/virtual/mac80211_hwsim.c:2353 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1842 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline] RIP: 0010:vprintk_emit+0x58f/0x7a0 kernel/printk/printk.c:2449 Code: 85 32 01 00 00 e8 81 84 1f 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 70 84 1f 00 eb 06 e8 69 84 1f 00 fb 48 c7 c7 40 ef d2 8d <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 b9 35 RSP: 0018:ffffc90003366660 EFLAGS: 00000246 RAX: ffffffff819e9127 RBX: ffffffff819e8fe4 RCX: 0000000000080000 RDX: ffffc9000e592000 RSI: 000000000007ffff RDI: ffffffff8dd2ef40 RBP: ffffc90003366770 R08: ffffffff8f5cac37 R09: 1ffffffff1eb9586 R10: dffffc0000000000 R11: fffffbfff1eb9587 R12: dffffc0000000000 R13: 1ffff9200066ccd0 R14: 0000000000000200 R15: 0000000000000037 _printk+0xcf/0x120 kernel/printk/printk.c:2475 netdev_info+0x10a/0x160 net/core/dev.c:12653 __bond_release_one+0x50b/0x10e0 drivers/net/bonding/bond_main.c:2567 do_set_master+0x312/0x6d0 net/core/rtnetlink.c:2932 do_setlink+0xcf0/0x41c0 net/core/rtnetlink.c:3150 rtnl_group_changelink net/core/rtnetlink.c:3775 [inline] __rtnl_newlink net/core/rtnetlink.c:3929 [inline] rtnl_newlink+0x149f/0x1c70 net/core/rtnetlink.c:4057 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6946 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:729 ____sys_sendmsg+0x505/0x830 net/socket.c:2617 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2671 __sys_sendmsg net/socket.c:2703 [inline] __do_sys_sendmsg net/socket.c:2708 [inline] __se_sys_sendmsg net/socket.c:2706 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2706 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7feabbf8eec9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007feaba1ac038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007feabc1e6180 RCX: 00007feabbf8eec9 RDX: 0000000000000000 RSI: 0000200000000280 RDI: 000000000000000b RBP: 00007feabc011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007feabc1e6218 R14: 00007feabc1e6180 R15: 00007feabc30fa28