INFO: task kworker/0:6:5957 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:6 state:D stack:21048 pid:5957 tgid:5957 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 hub_port_connect drivers/usb/core/hub.c:5464 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x21e5/0x4a20 drivers/usb/core/hub.c:5952 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13d2e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13d2e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e13d2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5581: #0: ffff8880336c40a0 (&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 5 locks held by kworker/1:3/5859: #0: ffff8881404a6548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff8881404a6548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000443fba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000443fba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888028ae5198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff888028ae5198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898 #3: ffff888028b38518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3251 [inline] #3: ffff888028b38518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5463 [inline] #3: ffff888028b38518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #3: ffff888028b38518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline] #3: ffff888028b38518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b8/0x4a20 drivers/usb/core/hub.c:5952 #4: ffff8880289cd468 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #4: ffff8880289cd468 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #4: ffff8880289cd468 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline] #4: ffff8880289cd468 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21e5/0x4a20 drivers/usb/core/hub.c:5952 5 locks held by kworker/0:6/5957: #0: ffff8881404a6548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff8881404a6548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc9000473fba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc9000473fba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888146fdf198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff888146fdf198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898 #3: ffff888028a7a518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3251 [inline] #3: ffff888028a7a518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5463 [inline] #3: ffff888028a7a518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #3: ffff888028a7a518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline] #3: ffff888028a7a518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b8/0x4a20 drivers/usb/core/hub.c:5952 #4: ffff8880289cd468 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #4: ffff8880289cd468 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #4: ffff8880289cd468 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline] #4: ffff8880289cd468 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21e5/0x4a20 drivers/usb/core/hub.c:5952 4 locks held by syz.1.1957/17300: #0: ffff8880244ec420 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508 #1: ffff888055e24748 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1025 [inline] #1: ffff888055e24748 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3360 [inline] #1: ffff888055e24748 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: do_renameat2+0x3b9/0xa50 fs/namei.c:5311 #2: ffff888055e23248 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #2: ffff888055e23248 (&sb->s_type->i_mutex_key#23){+.+.}-{4:4}, at: lock_two_nondirectories+0xe7/0x180 fs/inode.c:1232 #3: ffff888055e24048 (&sb->s_type->i_mutex_key#23/4){+.+.}-{4:4}, at: vfs_rename+0x665/0xe80 fs/namei.c:5187 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 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: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 71 23 00 f3 0f 1e fa fb f4 c8 e6 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8de07d80 EFLAGS: 000002c6 RAX: 722f4ff273df1200 RBX: ffffffff8196ac07 RCX: 722f4ff273df1200 RDX: 0000000000000001 RSI: ffffffff8d7f179a RDI: ffffffff8bc0d460 RBP: ffffffff8de07ea8 R08: ffff8880b8632fdb R09: 1ffff110170c65fb R10: dffffc0000000000 R11: ffffed10170c65fc R12: ffffffff8f9dbe70 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1bd2a40 FS: 0000000000000000(0000) GS:ffff888125d2b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000000014c0 CR3: 000000000df38000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e7/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 rest_init+0x2de/0x300 init/main.c:757 start_kernel+0x3ae/0x410 init/main.c:1111 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147