watchdog: BUG: soft lockup - CPU#0 stuck for 144s! [kworker/0:4:5256] Modules linked in: irq event stamp: 19426084 hardirqs last enabled at (19426083): [] ___slab_alloc+0xa4d/0x1ca0 mm/slub.c:4555 hardirqs last disabled at (19426084): [] sysvec_apic_timer_interrupt+0xe/0xb0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (19426074): [] do_softirq kernel/softirq.c:523 [inline] softirqs last enabled at (19426074): [] do_softirq+0xb2/0xf0 kernel/softirq.c:510 softirqs last disabled at (19426065): [] do_softirq kernel/softirq.c:523 [inline] softirqs last disabled at (19426065): [] do_softirq+0xb2/0xf0 kernel/softirq.c:510 CPU: 0 UID: 0 PID: 5256 Comm: kworker/0:4 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:trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:lock_acquire+0x4e/0x330 kernel/locking/lockdep.c:5831 Code: 48 8b 05 7d 03 47 0b 48 89 44 24 30 31 c0 66 90 65 8b 05 99 03 47 0b 83 f8 07 0f 87 a2 02 00 00 89 c0 48 0f a3 05 22 d5 48 09 <0f> 82 74 02 00 00 8b 35 ba e1 48 09 85 f6 0f 85 8d 00 00 00 48 8b RSP: 0018:ffffc90002dee810 EFLAGS: 00000297 RAX: 0000000000000000 RBX: ffffffff892cd6e0 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff892cd6e0 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000028629 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888268bf4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b33623ffc CR3: 00000000090a6000 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+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5657 [inline] __kmalloc_node_track_caller_noprof+0x351/0x8e0 mm/slub.c:5764 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:608 __alloc_skb+0x186/0x410 net/core/skbuff.c:690 __netdev_alloc_skb+0x7a/0x920 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+0x55/0x400 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+0x17e/0x11b0 drivers/net/wireless/ath/ath6kl/core.c:97 ath6kl_usb_probe+0xcee/0x1440 drivers/net/wireless/ath/ath6kl/usb.c:1168 usb_probe_interface+0x303/0xa80 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:581 [inline] really_probe+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031 device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x150 drivers/base/bus.c:574 device_add+0x116e/0x1980 drivers/base/core.c:3689 usb_set_configuration+0x1187/0x1e50 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 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+0x241/0xb20 drivers/base/dd.c:659 __driver_probe_device+0x1de/0x470 drivers/base/dd.c:801 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831 __device_attach_driver+0x1df/0x350 drivers/base/dd.c:959 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500 __device_attach+0x1e4/0x4e0 drivers/base/dd.c:1031 device_initial_probe+0xaa/0xc0 drivers/base/dd.c:1086 bus_probe_device+0x64/0x150 drivers/base/bus.c:574 device_add+0x116e/0x1980 drivers/base/core.c:3689 usb_new_device+0xd07/0x1a90 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+0x31bf/0x5420 drivers/usb/core/hub.c:5953 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 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: 17524 Comm: kworker/1:9 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events legacy_dvb_usb_read_remote_control RIP: 0010:__sanitizer_cov_trace_pc+0x41/0x70 kernel/kcov.c:217 Code: a9 00 01 ff 00 74 1d f6 c4 01 74 43 a9 00 00 0f 00 75 3c a9 00 00 f0 00 75 35 8b 82 64 15 00 00 85 c0 74 2b 8b 82 40 15 00 00 <83> f8 02 75 20 48 8b 8a 48 15 00 00 8b 92 44 15 00 00 48 8b 01 48 RSP: 0018:ffffc90015887870 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000017 RCX: 0000000000000000 RDX: ffff88811b8bba80 RSI: ffffffff815f5074 RDI: ffffc90015887904 RBP: 0000000000000003 R08: 0000000000000001 R09: 0000000000000000 R10: ffffc90015887900 R11: ffff88811b8bc528 R12: 1ffff92002b10f31 R13: 1ffff92002b10f16 R14: ffff888114791d40 R15: ffffc90015887a40 FS: 0000000000000000(0000) GS:ffff888268cf4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8db1e07dac CR3: 0000000134aee000 CR4: 00000000003506f0 Call Trace: nbcon_get_default_prio+0x14/0xa0 kernel/printk/nbcon.c:1430 printk_get_console_flush_type+0x1e/0x450 kernel/printk/internal.h:198 console_unlock+0x83/0x240 kernel/printk/printk.c:3357 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426 _printk+0xc7/0x100 kernel/printk/printk.c:2451 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline] m920x_rc_query+0x496/0x770 drivers/media/usb/dvb-usb/m920x.c:193 legacy_dvb_usb_read_remote_control+0x10c/0x4f0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246