watchdog: BUG: soft lockup - CPU#1 stuck for 144s! [kworker/1:1:43] Modules linked in: irq event stamp: 13179464 hardirqs last enabled at (13179463): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] hardirqs last enabled at (13179463): [] _raw_spin_unlock_irqrestore+0x52/0x80 kernel/locking/spinlock.c:194 hardirqs last disabled at (13179464): [] sysvec_apic_timer_interrupt+0xe/0xb0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (13179456): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (13179456): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (13179456): [] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 softirqs last disabled at (13179447): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (13179447): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (13179447): [] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 CPU: 1 UID: 0 PID: 43 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:lock_acquire+0x5e/0x330 kernel/locking/lockdep.c:5872 Code: 05 7b 34 3d 0b 83 f8 07 0f 87 a4 02 00 00 48 0f a3 05 06 aa 3e 09 0f 82 6f 02 00 00 8b 35 9e b6 3e 09 85 f6 0f 85 8a 00 00 00 <48> 8b 44 24 30 65 48 2b 05 1d 34 3d 0b 0f 85 b8 02 00 00 48 83 c4 RSP: 0018:ffffc900004e6860 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000005 RDX: 0000000000000000 RSI: ffffffff88dcbbf7 RDI: ffffffff878e97a0 RBP: ffffffff894da3a0 R08: 000000004312e230 R09: 0000000000000007 R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888268a6a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe7ebdc86c0 CR3: 00000000092a8000 CR4: 00000000003506f0 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:867 [inline] class_rcu_constructor include/linux/rcupdate.h:1195 [inline] unwind_next_frame+0xd1/0x1ea0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:415 kmalloc_noprof include/linux/slab.h:957 [inline] dummy_urb_enqueue+0xa3/0x880 drivers/usb/gadget/udc/dummy_hcd.c:1273 usb_hcd_submit_urb+0x26c/0x2150 drivers/usb/core/hcd.c:1542 usb_submit_urb+0x8aa/0x1910 drivers/usb/core/urb.c:587 ath6kl_usb_post_recv_transfers.constprop.0+0x204/0x3d0 drivers/net/wireless/ath/ath6kl/usb.c:450 ath6kl_usb_start_recv_pipes drivers/net/wireless/ath/ath6kl/usb.c:498 [inline] hif_start drivers/net/wireless/ath/ath6kl/usb.c:703 [inline] ath6kl_usb_power_on+0x8e/0x160 drivers/net/wireless/ath/ath6kl/usb.c:1062 ath6kl_hif_power_on drivers/net/wireless/ath/ath6kl/hif-ops.h:136 [inline] ath6kl_core_init+0x173/0x11b0 drivers/net/wireless/ath/ath6kl/core.c:97 ath6kl_usb_probe+0xcd0/0x13e0 drivers/net/wireless/ath/ath6kl/usb.c:1168 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x400 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1031 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x160 drivers/base/bus.c:574 device_add+0x11d9/0x1950 drivers/base/core.c:3689 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x400 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x340 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1031 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x160 drivers/base/bus.c:574 device_add+0x11d9/0x1950 drivers/base/core.c:3689 usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2695 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5953 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3421 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3802 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3821 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:3876 [inline] RIP: 0010:__lock_acquire+0x879/0x2630 kernel/locking/lockdep.c:5237 Code: 4d 0f af e7 49 c1 ec 2d 4a 8b 04 e5 60 62 0e 90 4e 8d 34 e5 60 62 0e 90 48 85 c0 74 1f 48 83 e8 08 48 85 c0 74 16 48 8b 50 18 <49> 39 d7 0f 84 a7 fd ff ff 48 8b 40 08 48 85 c0 75 e1 8b 0d ef 7b RSP: 0018:ffffc90000007d80 EFLAGS: 00000086 RAX: ffffffff8cd0f3c0 RBX: ffff888101ab8b48 RCX: 0000000000000004 RDX: 3adb410964a972cd RSI: 000000007fde9a0a RDI: 0000000047117bb8 RBP: ffff888101ab8000 R08: 00000000c732e1ae R09: 0000000000000053 R10: ffffffff93d9c308 R11: 0000000000000001 R12: 000000000003e8d0 R13: 0000000000000053 R14: ffffffff902da8e0 R15: 3adb410964a972cd FS: 0000000000000000(0000) GS:ffff88826896a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa2f65a0980 CR3: 000000012a2ec000 CR4: 00000000003506f0 Call Trace: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x17c/0x330 kernel/locking/lockdep.c:5825 seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline] ktime_get_update_offsets_now+0x8f/0x4d0 kernel/time/timekeeping.c:2570 hrtimer_update_base kernel/time/hrtimer.c:633 [inline] hrtimer_interrupt+0x13e/0x8c0 kernel/time/hrtimer.c:1885 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x109/0x3c0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x8a/0xb0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2037 [inline] RIP: 0010:vprintk_emit+0x553/0x6b0 kernel/printk/printk.c:2425 Code: 00 4d 85 ed 0f 85 1b 01 00 00 e8 78 54 20 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 46 4f 20 00 48 85 ed 0f 85 27 01 00 00 58 54 20 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00 RSP: 0018:ffffc9000009f4e8 EFLAGS: 00000283 RAX: 000000000008d71c RBX: 0000000000000041 RCX: ffffc90008c03000 RDX: 0000000000100000 RSI: ffffffff8190e8c4 RDI: ffff888101ab8000 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff92000013e9f R13: 0000000000000200 R14: ffff8881032e57c0 R15: ffffc9000009f6b0 dev_vprintk_emit+0x394/0x3e0 drivers/base/core.c:4914 dev_printk_emit+0xd2/0x10d drivers/base/core.c:4925 __dev_printk+0xcb/0x100 drivers/base/core.c:4937 _dev_info+0xef/0x127 drivers/base/core.c:4983 announce_device drivers/usb/core/hub.c:2413 [inline] usb_new_device.cold+0x3df/0x115c drivers/usb/core/hub.c:2676 hub_port_connect drivers/usb/core/hub.c:5567 [inline] hub_port_connect_change drivers/usb/core/hub.c:5707 [inline] port_event drivers/usb/core/hub.c:5871 [inline] hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5953 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3421 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246