INFO: task kworker/0:6:5240 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:6 state:D stack:0 pid:5240 tgid:5240 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:6016 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7870 __schedule_loop kernel/sched/core.c:7951 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7966 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8023 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285 usb_audio_probe+0x39d/0x1d60 sound/usb/card.c:887 usb_probe_interface+0x6ac/0xc00 drivers/usb/core/driver.c:400 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2d8/0x890 drivers/base/dd.c:657 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957 bus_for_each_drv+0x267/0x300 drivers/base/bus.c:459 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534 device_add+0x80c/0xbf0 drivers/base/core.c:3692 usb_set_configuration+0x1acf/0x20b0 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x95/0x160 drivers/usb/core/generic.c:254 usb_probe_device+0x1d1/0x380 drivers/usb/core/driver.c:295 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2d8/0x890 drivers/base/dd.c:657 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957 bus_for_each_drv+0x267/0x300 drivers/base/bus.c:459 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534 device_add+0x80c/0xbf0 drivers/base/core.c:3692 usb_new_device+0x9f8/0x15b0 drivers/usb/core/hub.c:2703 hub_port_connect drivers/usb/core/hub.c:5574 [inline] hub_port_connect_change drivers/usb/core/hub.c:5714 [inline] port_event drivers/usb/core/hub.c:5878 [inline] hub_event+0x30c6/0x4700 drivers/usb/core/hub.c:5960 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0x7d1/0x1020 kernel/workqueue.c:3319 worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400 kthread+0x2c6/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 1a36ed5f0b44f46e7eaed3953ba11d0fea6dce7e Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xdad/0xf00 kernel/hung_task.c:423 kthread+0x2c6/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 36 Comm: kauditd Not tainted syzkaller #0 1a36ed5f0b44f46e7eaed3953ba11d0fea6dce7e Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:cpus_share_cache+0x6e/0x130 kernel/sched/core.c:4471 Code: 0c 4c 89 f7 89 f3 e8 f1 73 83 00 89 de 48 c7 c3 bc 8f 02 00 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 77 44 8b 23 <48> 63 de 83 fe 08 0f 83 8b 00 00 00 4c 8d 34 dd 80 cb 1f 87 4c 89 RSP: 0018:ffffc90000007a70 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff8881f6f28fbc RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffffc90000007a90 R08: ffff888101a6ed2f R09: 1ffff1102034dda5 R10: dffffc0000000000 R11: ffffed102034dda6 R12: 0000000000000000 R13: 0000000000000001 R14: ffffffff871fcb88 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbb485e9f00 CR3: 000000010df62000 CR4: 00000000003526b0 Call Trace: select_idle_sibling kernel/sched/fair.c:8128 [inline] select_task_rq_fair+0xc79/0x2450 kernel/sched/fair.c:8899 select_task_rq kernel/sched/core.c:3774 [inline] try_to_wake_up+0xc2c/0x1db0 kernel/sched/core.c:4901 wake_up_process+0x14/0x20 kernel/sched/core.c:5050 hrtimer_wakeup+0x52/0x70 kernel/time/hrtimer.c:1989 __run_hrtimer kernel/time/hrtimer.c:1753 [inline] __hrtimer_run_queues+0x3c6/0x9e0 kernel/time/hrtimer.c:1817 hrtimer_interrupt+0x37e/0xf00 kernel/time/hrtimer.c:1879 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x8e/0x2a0 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x7d/0x90 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2076 [inline] RIP: 0010:vprintk_emit+0x547/0x650 kernel/printk/printk.c:2461 Code: 81 e6 00 02 00 00 31 ff e8 16 cb 1e 00 48 81 e3 00 02 00 00 75 07 e8 28 c6 1e 00 eb 06 e8 21 c6 1e 00 fb c6 05 a9 14 53 07 00 31 fd ff ff e8 0f c6 1e 00 e9 94 fe ff ff 41 ff ce bf 58 89 41 RSP: 0018:ffffc9000025fac0 EFLAGS: 00000293 RAX: ffffffff8168e68f RBX: 0000000000000200 RCX: ffff88810367b900 RDX: 0000000000000000 RSI: 0000000000000200 RDI: 0000000000000000 RBP: ffffc9000025fb88 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200004bf48 R12: 1ffff9200004bf5c R13: 00000000000000ee R14: 0000000000000000 R15: dffffc0000000000 vprintk_default+0x2a/0x40 kernel/printk/printk.c:2477 vprintk+0x93/0xa0 kernel/printk/printk_safe.c:75 _printk+0xde/0x140 kernel/printk/printk.c:2487 kauditd_printk_skb kernel/audit.c:546 [inline] kauditd_hold_skb+0x1cc/0x230 kernel/audit.c:581 kauditd_send_queue+0x2c7/0x310 kernel/audit.c:766 kauditd_thread+0x4e0/0x740 kernel/audit.c:890 kthread+0x2c6/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244