------------[ cut here ]------------ workqueue: cannot queue hci_cmd_timeout on wq hci0 WARNING: kernel/workqueue.c:2271 at __queue_work+0xd20/0xf90 kernel/workqueue.c:2269, CPU#1: kworker/u8:22/6129 Modules linked in: CPU: 1 UID: 0 PID: 6129 Comm: kworker/u8:22 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:__queue_work+0xd4b/0xf90 kernel/workqueue.c:2269 Code: 83 c5 18 4c 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ef e8 e6 68 9d 00 49 8b 75 00 49 81 c7 78 01 00 00 4c 89 f7 4c 89 fa <67> 48 0f b9 3a 48 83 c4 58 5b 41 5c 41 5d 41 5e 41 5f 5d e9 3d 3a RSP: 0018:ffffc90000a08b10 EFLAGS: 00010086 RAX: 1ffff1100a96f951 RBX: 0000000000000008 RCX: ffff88802c823d00 RDX: ffff888030393978 RSI: ffffffff8a55b780 RDI: ffffffff8f851210 RBP: 0000000000000100 R08: ffffffff8f822a77 R09: 1ffffffff1f0454e R10: dffffc0000000000 R11: ffffffff818ab820 R12: dffffc0000000000 R13: ffff888054b7ca88 R14: ffffffff8f851210 R15: ffff888030393978 FS: 0000000000000000(0000) GS:ffff888125f31000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2dffaff8 CR3: 0000000076a60000 CR4: 00000000003526f0 Call Trace: call_timer_fn+0x16e/0x590 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1794 [inline] __run_timers kernel/time/timer.c:2373 [inline] __run_timer_base+0x646/0x860 kernel/time/timer.c:2385 run_timer_base kernel/time/timer.c:2394 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2404 handle_softirqs+0x27d/0x850 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:727 irq_exit_rcu+0x9/0x30 kernel/softirq.c:743 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] RIP: 0010:rcu_is_watching+0x10/0xb0 kernel/rcu/tree.c:751 Code: 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 65 ff 05 60 4c d7 10 4b 7a b4 09 89 c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df RSP: 0018:ffffc9000b8873f8 EFLAGS: 00000283 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8df41a60 RBP: ffffffff81743f85 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc9000b8875d8 R11: ffffffff81ada980 R12: 0000000000000002 R13: ffffffff8df41a60 R14: 0000000000000000 R15: 0000000000000000 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x5f/0x340 kernel/locking/lockdep.c:5831 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+0xc2/0x23d0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6670 [inline] kmem_cache_free+0x197/0x620 mm/slub.c:6781 nsim_dev_trap_report drivers/net/netdevsim/dev.c:891 [inline] nsim_dev_trap_report_work+0x7cf/0xb80 drivers/net/netdevsim/dev.c:921 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 ---------------- Code disassembly (best guess): 0: 83 c5 18 add $0x18,%ebp 3: 4c 89 e8 mov %r13,%rax 6: 48 c1 e8 03 shr $0x3,%rax a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) f: 74 08 je 0x19 11: 4c 89 ef mov %r13,%rdi 14: e8 e6 68 9d 00 call 0x9d68ff 19: 49 8b 75 00 mov 0x0(%r13),%rsi 1d: 49 81 c7 78 01 00 00 add $0x178,%r15 24: 4c 89 f7 mov %r14,%rdi 27: 4c 89 fa mov %r15,%rdx * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 48 83 c4 58 add $0x58,%rsp 33: 5b pop %rbx 34: 41 5c pop %r12 36: 41 5d pop %r13 38: 41 5e pop %r14 3a: 41 5f pop %r15 3c: 5d pop %rbp 3d: e9 .byte 0xe9 3e: 3d .byte 0x3d 3f: 3a .byte 0x3a