watchdog: BUG: soft lockup - CPU#0 stuck for 143s! [kworker/0:5:5327] Modules linked in: irq event stamp: 15225220 hardirqs last enabled at (15225219): [] __local_bh_enable_ip+0x9e/0x120 kernel/softirq.c:455 hardirqs last disabled at (15225220): [] sysvec_apic_timer_interrupt+0xe/0xb0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (15225218): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last enabled at (15225218): [] __alloc_skb+0x35d/0x410 net/core/skbuff.c:672 softirqs last disabled at (15225216): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last disabled at (15225216): [] __alloc_skb+0x35d/0x410 net/core/skbuff.c:672 CPU: 0 UID: 0 PID: 5327 Comm: kworker/0:5 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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 a8 3e 09 0f 82 6f 02 00 00 8b 35 9e b4 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:ffffc90001f7e7f0 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000005 RDX: 0000000000000000 RSI: ffffffff88dcb9c1 RDI: ffffffff878e97a0 RBP: ffffffff894da3a0 R08: 000000004d67fd8b R09: 0000000000000007 R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88826896a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f608de01000 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 __unwind_start+0x3d1/0x7f0 arch/x86/kernel/unwind_orc.c:773 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0x73/0xf0 arch/x86/kernel/stacktrace.c:24 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 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6e/0x70 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_node_noprof+0x292/0x7d0 mm/slub.c:5315 __alloc_skb+0x156/0x410 net/core/skbuff.c:679 __netdev_alloc_skb+0x7a/0x8f0 net/core/skbuff.c:754 netdev_alloc_skb include/linux/skbuff.h:3484 [inline] dev_alloc_skb include/linux/skbuff.h:3497 [inline] ath6kl_usb_post_recv_transfers.constprop.0+0x55/0x3d0 drivers/net/wireless/ath/ath6kl/usb.c:428 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 4a a3 01 e9 53 e3 02 00 0f 1f 00 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 53 c3 12 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc9000013fe00 EFLAGS: 00000242 RAX: 0000000000a68967 RBX: ffff888101ecba80 RCX: ffffffff87539cd5 RDX: 0000000000000000 RSI: ffffffff88dec6f5 RDI: ffffffff878e97a0 RBP: 0000000000000001 R08: 0000000000000001 R09: ffffed103eae66c5 R10: ffff8881f573362b R11: 0000000000000000 R12: ffffed10203d9750 R13: 0000000000000001 R14: ffffffff8accd3d0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888268a6a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555558641908 CR3: 000000012477c000 CR4: 00000000003506f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x35b/0x4b0 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x148