------------[ cut here ]------------ workqueue: cannot queue hci_cmd_timeout on wq hci0 WARNING: kernel/workqueue.c:2298 at __queue_work+0xd3f/0x1040 kernel/workqueue.c:2296, CPU#0: kworker/u4:8/1063 Modules linked in: CPU: 0 UID: 0 PID: 1063 Comm: kworker/u4:8 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:__queue_work+0xd67/0x1040 kernel/workqueue.c:2296 Code: a6 0e 49 8d 7d 18 48 89 f8 48 c1 e8 03 42 80 3c 20 00 74 05 e8 4a 66 a5 00 49 8b 75 18 49 81 c7 70 01 00 00 4c 89 f7 4c 89 fa <67> 48 0f b9 3a 4c 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ef RSP: 0018:ffffc90000007bd8 EFLAGS: 00010082 RAX: 1ffff1100256c14e RBX: 0000000000000008 RCX: ffff888036880000 RDX: ffff88803fdaf170 RSI: ffffffff8a9e8e90 RDI: ffffffff9033fe70 RBP: 0000000000000100 R08: ffffffff9030fff7 R09: 1ffffffff2061ffe R10: dffffc0000000000 R11: ffffffff818d38b0 R12: dffffc0000000000 R13: ffff888012b60a58 R14: ffffffff9033fe70 R15: ffff88803fdaf170 FS: 0000000000000000(0000) GS:ffff88808c87b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055558b38dc48 CR3: 000000001276e000 CR4: 0000000000352ef0 Call Trace: call_timer_fn+0x192/0x5e0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1794 [inline] __run_timers kernel/time/timer.c:2374 [inline] __run_timer_base+0x67e/0x8b0 kernel/time/timer.c:2386 run_timer_base kernel/time/timer.c:2395 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872 Code: ff ff ff e8 21 be 09 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 db a8 98 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 80 b1 0c 0a cc 48 8d 3d a8 b6 92 RSP: 0018:ffffc90001437078 EFLAGS: 00000286 RAX: f8198f02c7592400 RBX: 0000000000000000 RCX: 0000000000000046 RDX: 0000000018f0521e RSI: ffffffff8e2211c5 RDI: ffffffff8c28cee0 RBP: ffffffff8176e256 R08: ffffffff8176e256 R09: ffffffff8e95cce0 R10: ffffc900014371d8 R11: ffffffff81b0e040 R12: 0000000000000002 R13: ffffffff8e95cce0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] class_rcu_constructor include/linux/rcupdate.h:1181 [inline] unwind_next_frame+0xc3/0x2550 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5296 [inline] __kmalloc_node_track_caller_noprof+0x4db/0x7b0 mm/slub.c:5408 kmalloc_reserve net/core/skbuff.c:635 [inline] __alloc_skb+0x2c1/0x7d0 net/core/skbuff.c:713 alloc_skb include/linux/skbuff.h:1383 [inline] mld_newpack+0x14c/0xc90 net/ipv6/mcast.c:1775 add_grhead+0x5a/0x2a0 net/ipv6/mcast.c:1886 add_grec+0x1452/0x1740 net/ipv6/mcast.c:2025 mld_send_initial_cr+0x288/0x550 net/ipv6/mcast.c:2268 ipv6_mc_dad_complete+0x88/0x540 net/ipv6/mcast.c:2279 addrconf_dad_completed+0x8a7/0xe60 net/ipv6/addrconf.c:4352 addrconf_dad_work+0xc5e/0x14c0 net/ipv6/addrconf.c:-1 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 49 8d 7d 18 lea 0x18(%r13),%rdi 4: 48 89 f8 mov %rdi,%rax 7: 48 c1 e8 03 shr $0x3,%rax b: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) 10: 74 05 je 0x17 12: e8 4a 66 a5 00 call 0xa56661 17: 49 8b 75 18 mov 0x18(%r13),%rsi 1b: 49 81 c7 70 01 00 00 add $0x170,%r15 22: 4c 89 f7 mov %r14,%rdi 25: 4c 89 fa mov %r15,%rdx * 28: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2d: 4c 89 e8 mov %r13,%rax 30: 48 c1 e8 03 shr $0x3,%rax 34: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) 39: 74 08 je 0x43 3b: 4c 89 ef mov %r13,%rdi