INFO: task syz.1.1094:10030 blocked for more than 163 seconds. Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1094 state:D stack:25016 pid:10030 tgid:10029 ppid:5903 task_flags:0x480040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790 __schedule_loop kernel/sched/core.c:6868 [inline] schedule+0x165/0x360 kernel/sched/core.c:6883 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148 i2c_del_adapter+0x581/0x6e0 drivers/i2c/i2c-core-base.c:1811 em28xx_i2c_unregister+0x4b/0x60 drivers/media/usb/em28xx/em28xx-i2c.c:1027 em28xx_release_resources+0x14c/0x240 drivers/media/usb/em28xx/em28xx-cards.c:3536 em28xx_usb_disconnect+0x19f/0x2f0 drivers/media/usb/em28xx/em28xx-cards.c:4201 usb_unbind_interface+0x26b/0x8f0 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4d9/0x7c0 drivers/base/dd.c:1295 bus_remove_device+0x34d/0x410 drivers/base/bus.c:579 device_del+0x511/0x8e0 drivers/base/core.c:3881 usb_disable_device+0x3e9/0x8a0 drivers/usb/core/message.c:1418 usb_disconnect+0x330/0x950 drivers/usb/core/hub.c:2344 hub_quiesce+0x171/0x330 drivers/usb/core/hub.c:1409 hub_disconnect+0xc8/0x470 drivers/usb/core/hub.c:1815 usb_unbind_interface+0x26b/0x8f0 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4d9/0x7c0 drivers/base/dd.c:1295 proc_disconnect_claim+0x2e1/0x350 drivers/usb/core/devio.c:2492 usbdev_do_ioctl drivers/usb/core/devio.c:2783 [inline] usbdev_ioctl+0x131b/0x20c0 drivers/usb/core/devio.c:2827 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 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: 0033:0x7fdbfcf8e929 RSP: 002b:00007fdbfdecf038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fdbfd1b5fa0 RCX: 00007fdbfcf8e929 RDX: 0000200000000000 RSI: 000000008108551b RDI: 0000000000000003 RBP: 00007fdbfd010b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fdbfd1b5fa0 R15: 00007fdbfd2dfa28 INFO: task syz.1.1094:10033 blocked for more than 165 seconds. Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1094 state:D stack:28904 pid:10033 tgid:10029 ppid:5903 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790 __schedule_loop kernel/sched/core.c:6868 [inline] schedule+0x165/0x360 kernel/sched/core.c:6883 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6940 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747 device_lock include/linux/device.h:884 [inline] usbdev_do_ioctl drivers/usb/core/devio.c:2611 [inline] usbdev_ioctl+0x140/0x20c0 drivers/usb/core/devio.c:2827 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 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: 0033:0x7fdbfcf8e929 RSP: 002b:00007fdbfdeae038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fdbfd1b6080 RCX: 00007fdbfcf8e929 RDX: 00002000000006c0 RSI: 00000000c0185500 RDI: 0000000000000003 RBP: 00007fdbfd010b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fdbfd1b6080 R15: 00007fdbfd2dfa28 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13f160 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by getty/5606: #0: ffff88814ca1c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/1:1/5888: 4 locks held by kworker/u8:0/5912: 5 locks held by kworker/0:5/5989: #0: ffff888020ada148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888020ada148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc900047dfbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900047dfbc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 #2: ffff88802853c198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #2: ffff88802853c198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5894 #3: ffff88802853f510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3251 [inline] #3: ffff88802853f510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5463 [inline] #3: ffff88802853f510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #3: ffff88802853f510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5866 [inline] #3: ffff88802853f510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21a3/0x4a00 drivers/usb/core/hub.c:5948 #4: ffff8880282b6068 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #4: ffff8880282b6068 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #4: ffff8880282b6068 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5866 [inline] #4: ffff8880282b6068 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21cb/0x4a00 drivers/usb/core/hub.c:5948 4 locks held by kworker/0:6/5999: 1 lock held by syz.0.1064/9931: 5 locks held by syz.1.1094/10030: #0: ffff888028409198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #0: ffff888028409198 (&dev->mutex){....}-{4:4}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2611 [inline] #0: ffff888028409198 (&dev->mutex){....}-{4:4}, at: usbdev_ioctl+0x140/0x20c0 drivers/usb/core/devio.c:2827 #1: ffff888028432160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #1: ffff888028432160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #1: ffff888028432160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x7c0 drivers/base/dd.c:1292 #2: ffff888026fde198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #2: ffff888026fde198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xf8/0x950 drivers/usb/core/hub.c:2335 #3: ffff888024806160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #3: ffff888024806160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #3: ffff888024806160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x7c0 drivers/base/dd.c:1292 #4: ffff8880118a1b88 (&dev->lock#3){+.+.}-{4:4}, at: em28xx_release_resources+0x75/0x240 drivers/media/usb/em28xx/em28xx-cards.c:3530 1 lock held by syz.1.1094/10033: #0: ffff888028409198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #0: ffff888028409198 (&dev->mutex){....}-{4:4}, at: usbdev_do_ioctl drivers/usb/core/devio.c:2611 [inline] #0: ffff888028409198 (&dev->mutex){....}-{4:4}, at: usbdev_ioctl+0x140/0x20c0 drivers/usb/core/devio.c:2827 1 lock held by syz.2.1530/11639: #0: ffff888028409198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #0: ffff888028409198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 1 lock held by syz.3.1618/12018: #0: ffffffff8f51d808 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline] #0: ffffffff8f51d808 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3396 1 lock held by syz.6.1626/12048: #0: ffffffff8f51d808 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline] #0: ffffffff8f51d808 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3396 1 lock held by syz.4.1629/12059: #0: ffffffff8f51d808 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline] #0: ffffffff8f51d808 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3396 2 locks held by syz.5.1630/12063: #0: ffffffff8f51d808 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline] #0: ffffffff8f51d808 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3396 #1: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #1: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 979 Comm: kworker/0:2 Not tainted 6.16.0-rc5-syzkaller-00038-g733923397fd9 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_power_efficient gc_worker RIP: 0010:check_preemption_disabled+0x2d/0x120 lib/smp_processor_id.c:55 Code: 41 56 53 48 83 ec 10 65 48 8b 05 0e 2e 31 07 48 89 44 24 08 65 8b 05 16 2e 31 07 65 8b 0d 0b 2e 31 07 f7 c1 ff ff ff 7f 74 23 <65> 48 8b 0d eb 2d 31 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 RSP: 0018:ffffc9000414f7f0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffffffff899f78f8 RCX: 0000000080000000 RDX: 0000000000000000 RSI: ffffffff8d9e930d RDI: ffffffff8be29dc0 RBP: ffffc9000414f910 R08: 0000000000000000 R09: ffffffff89a02824 R10: dffffc0000000000 R11: fffffbfff1f43dff R12: 0000000000000200 R13: ffff8880250a7018 R14: 1ffff92000829f0c R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000404030 CR3: 000000000df38000 CR4: 00000000003526f0 Call Trace: lockdep_hardirqs_off+0xab/0x110 kernel/locking/lockdep.c:4498 trace_hardirqs_off+0x12/0x40 kernel/trace/trace_preemptirq.c:104 seqcount_lockdep_reader_access+0xe8/0x1c0 include/linux/seqlock.h:71 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:333 [inline] gc_worker+0x308/0x1380 net/netfilter/nf_conntrack_core.c:1537 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245