INFO: task kworker/1:2:310 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:310 tgid:310 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:6026 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7880 __schedule_loop kernel/sched/core.c:7961 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7976 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8033 __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+0x264/0x300 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:2268 usb_generic_driver_probe+0x95/0x160 drivers/usb/core/generic.c:254 usb_probe_device+0x1d4/0x380 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+0x264/0x300 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:3261 [inline] process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3342 worker_thread+0xc51/0x1370 kernel/workqueue.c:3423 kthread+0x2c9/0x370 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 INFO: task kworker/1:6:542 blocked for more than 123 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:6 state:D stack:0 pid:542 tgid:542 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:6026 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7880 __schedule_loop kernel/sched/core.c:7961 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7976 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8033 __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+0x264/0x300 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:2268 usb_generic_driver_probe+0x95/0x160 drivers/usb/core/generic.c:254 usb_probe_device+0x1d4/0x380 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+0x264/0x300 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:3261 [inline] process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3342 worker_thread+0xc51/0x1370 kernel/workqueue.c:3423 kthread+0x2c9/0x370 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 INFO: task kworker/0:5:641 blocked for more than 123 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:5 state:D stack:0 pid:641 tgid:641 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:6026 [inline] __schedule+0x1399/0x1fa0 kernel/sched/core.c:7880 __schedule_loop kernel/sched/core.c:7961 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7976 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8033 __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+0x264/0x300 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:2268 usb_generic_driver_probe+0x95/0x160 drivers/usb/core/generic.c:254 usb_probe_device+0x1d4/0x380 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+0x264/0x300 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:3261 [inline] process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3342 worker_thread+0xc51/0x1370 kernel/workqueue.c:3423 kthread+0x2c9/0x370 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 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 2d55ab0d08d30afb2392ba3a535ea3e888ff1e10 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 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+0x2c9/0x370 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: kworker/1:0 Not tainted syzkaller #0 2d55ab0d08d30afb2392ba3a535ea3e888ff1e10 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events drain_vmap_area_work RIP: 0010:__raw_callee_save___pv_queued_spin_unlock+0x14/0x1d Code: cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 48 89 e5 52 b8 01 00 00 00 31 d2 f0 0f b0 17 <75> 07 5a 5d e9 43 30 00 00 56 0f b6 f0 e8 9a ff ff ff 5e 5a 5d c3 RSP: 0018:ffffc90000207770 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffffff87e3e358 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffff8881f6f72244 RDI: ffff8881f6f72240 RBP: ffffc90000207778 R08: ffff8881f6f72240 R09: 1ffff1103edee448 R10: 1ffff1103edee44b R11: 0000000000000fda R12: 0000000000000000 R13: ffff8881f6f72240 R14: 1ffff92000040efc R15: ffffffff87e3e300 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffef645d048 CR3: 000000011baf8000 CR4: 00000000003526b0 Call Trace: pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:589 [inline] queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline] do_raw_spin_unlock include/linux/spinlock.h:204 [inline] __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_unlock+0x45/0x60 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] free_unref_page+0x589/0xf80 mm/page_alloc.c:2910 __free_pages+0x6b/0x3b0 mm/page_alloc.c:5399 free_pages+0x86/0x90 mm/page_alloc.c:5412 kasan_depopulate_vmalloc_pte+0x79/0xa0 mm/kasan/shadow.c:408 apply_to_pte_range mm/memory.c:2837 [inline] apply_to_pmd_range mm/memory.c:2881 [inline] apply_to_pud_range mm/memory.c:2917 [inline] apply_to_p4d_range mm/memory.c:2953 [inline] __apply_to_page_range+0x7c2/0xd00 mm/memory.c:2989 apply_to_existing_page_range+0x3c/0x50 mm/memory.c:3022 kasan_release_vmalloc+0xa6/0xd0 mm/kasan/shadow.c:529 kasan_release_vmalloc_node mm/vmalloc.c:2215 [inline] purge_vmap_node+0x243/0x8c0 mm/vmalloc.c:2237 __purge_vmap_area_lazy+0x614/0x8d0 mm/vmalloc.c:2328 drain_vmap_area_work+0x29/0x50 mm/vmalloc.c:2362 process_one_work kernel/workqueue.c:3261 [inline] process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3342 worker_thread+0xc51/0x1370 kernel/workqueue.c:3423 kthread+0x2c9/0x370 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