INFO: task kworker/1:2:306 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:2     state:D stack:0     pid:306   tgid:306   ppid:2      flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 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
 </TASK>
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 e45d454b0e2a0f603ce2cd14a9c0ffbdd9387507
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
 <TASK>
 __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
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 e45d454b0e2a0f603ce2cd14a9c0ffbdd9387507
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:106
Code: cc cc cc cc cc cc cc b8 75 b2 32 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 53 fb 45 00 55 48 89 e5 fb f4 <5d> c3 cc cc cc cc cc cc cc cc cc cc cc b8 00 00 00 00 90 90 90 90
RSP: 0018:ffffc900001a7e00 EFLAGS: 000002c6
RAX: ffff8881f6f00000 RBX: ffff88810366b900 RCX: ffffffff85a15bcd
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000110134
RBP: ffffc900001a7e00 R08: ffff8881f6f39773 R09: 1ffff1103ede72ee
R10: dffffc0000000000 R11: ffffed103ede72ef R12: 1ffff110206cd720
R13: 0000000000000001 R14: 0000000000000000 R15: ffffffff87ec1b68
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa24c5e92f8 CR3: 000000012cb1a000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:112 [inline]
 default_idle+0x17/0x30 arch/x86/kernel/process.c:754
 arch_cpu_idle+0xd/0x20 arch/x86/kernel/process.c:791
 default_idle_call+0x3e/0x80 kernel/sched/idle.c:117
 cpuidle_idle_call kernel/sched/idle.c:185 [inline]
 do_idle+0x19f/0x4b0 kernel/sched/idle.c:326
 cpu_startup_entry+0x47/0x60 kernel/sched/idle.c:424
 start_secondary+0x12e/0x140 arch/x86/kernel/smpboot.c:314
 common_startup_64+0x13b/0x157
 </TASK>