watchdog: BUG: soft lockup - CPU#0 stuck for 143s! [kworker/0:5:5253] Modules linked in: irq event stamp: 16698118 hardirqs last enabled at (16698117): [] ___slab_alloc+0x892/0x1ca0 mm/slub.c:4536 hardirqs last disabled at (16698118): [] sysvec_apic_timer_interrupt+0xe/0xb0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (16698112): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (16698112): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (16698112): [] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 softirqs last disabled at (16698103): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (16698103): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (16698103): [] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 CPU: 0 UID: 0 PID: 5253 Comm: kworker/0:5 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:rcu_read_unlock include/linux/rcupdate.h:895 [inline] RIP: 0010:class_rcu_destructor include/linux/rcupdate.h:1195 [inline] RIP: 0010:unwind_next_frame+0x745/0x1ea0 arch/x86/kernel/unwind_orc.c:495 Code: ff 48 c7 c2 40 93 66 87 be 64 03 00 00 48 c7 c7 a0 93 66 87 c6 05 a8 d6 4f 09 01 e8 a5 a9 1e 00 e9 9f f9 ff ff e8 ab 81 27 00 <84> c0 0f 85 63 fc ff ff e8 0e 71 e4 05 85 c0 0f 84 56 fc ff ff 80 RSP: 0018:ffffc90003c16320 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffc90003c163e0 RCX: ffffffff8b2dd901 RDX: 0000000000000000 RSI: ffffffff878e9720 RDI: ffffffff88f6cbe0 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000007 R10: 0000000000000200 R11: 0000000000006f49 R12: ffffc90003c16430 R13: ffffc90003c163e0 R14: ffffc90003c163e0 R15: ffffc90003c16414 FS: 0000000000000000(0000) GS:ffff88826896a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5933881000 CR3: 0000000117558000 CR4: 00000000003506f0 Call Trace: __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 save_stack+0x162/0x1e0 mm/page_owner.c:165 __set_page_owner+0x8c/0x540 mm/page_owner.c:341 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1e1/0x250 mm/page_alloc.c:1884 prep_new_page mm/page_alloc.c:1892 [inline] get_page_from_freelist+0xd57/0x3b20 mm/page_alloc.c:3945 __alloc_frozen_pages_noprof+0x269/0x2230 mm/page_alloc.c:5240 alloc_pages_mpol+0xe8/0x410 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x2c4/0x440 mm/slub.c:3302 ___slab_alloc+0xda3/0x1ca0 mm/slub.c:4656 __slab_alloc.isra.0+0x63/0x110 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __kmalloc_cache_noprof+0x4ee/0x7e0 mm/slub.c:5771 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 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 01/24/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 3a 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 b3 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: 0000000000758737 RBX: ffff888101ecba80 RCX: ffffffff8753acd5 RDX: 0000000000000000 RSI: ffffffff88dec92b RDI: ffffffff878e97a0 RBP: 0000000000000001 R08: 0000000000000001 R09: ffffed103eae66c5 R10: ffff8881f573362b R11: 0000000000000000 R12: ffffed10203d9750 R13: 0000000000000001 R14: ffffffff8accd5d0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888268a6a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f59334c4180 CR3: 0000000130d96000 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