syzbot

watchdog: BUG: soft lockup - CPU#0 stuck for 121s! [syz.6.12639:13935]
Modules linked in:
irq event stamp: 13075463
hardirqs last  enabled at (13075462): [<ffffffff8badef2e>] irqentry_exit+0x59e/0x620 kernel/entry/common.c:242
hardirqs last disabled at (13075463): [<ffffffff8badd93e>] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1056
softirqs last  enabled at (12664784): [<ffffffff8188026f>] __do_softirq kernel/softirq.c:656 [inline]
softirqs last  enabled at (12664784): [<ffffffff8188026f>] invoke_softirq kernel/softirq.c:496 [inline]
softirqs last  enabled at (12664784): [<ffffffff8188026f>] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
softirqs last disabled at (12664787): [<ffffffff8188026f>] __do_softirq kernel/softirq.c:656 [inline]
softirqs last disabled at (12664787): [<ffffffff8188026f>] invoke_softirq kernel/softirq.c:496 [inline]
softirqs last disabled at (12664787): [<ffffffff8188026f>] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
CPU: 0 UID: 0 PID: 13935 Comm: syz.6.12639 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x27/0x90 kernel/kcov.c:321
Code: 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d 68 2d 56 11 65 8b 15 89 2d 56 11 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 <83> b9 94 16 00 00 00 74 4e 8b 91 70 16 00 00 83 fa 03 75 43 48 8b
RSP: 0018:ffffc90000007288 EFLAGS: 00000246
RAX: ffffffff81f8e016 RBX: 0000000000000103 RCX: ffff888045a3bd00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007400 R08: ffffc90000007598 R09: 0000000000000000
R10: ffffc900000075f8 R11: fffff52000000ec1 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff888045a3bd00 R15: dffffc0000000000
FS:  00007f46fe7776c0(0000) GS:ffff888125463000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f46fdbed700 CR3: 0000000030336000 CR4: 00000000003526f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000200000000300
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 interrupt_context_level include/linux/preempt.h:96 [inline]
 get_recursion_context kernel/events/internal.h:215 [inline]
 perf_swevent_get_recursion_context+0x56/0x100 kernel/events/core.c:11018
 perf_trace_buf_alloc+0x43/0x280 kernel/trace/trace_event_perf.c:410
 do_perf_trace_lock include/trace/events/lock.h:50 [inline]
 perf_trace_lock+0x1a0/0x410 include/trace/events/lock.h:50
 __do_trace_lock_release include/trace/events/lock.h:69 [inline]
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0x392/0x3d0 kernel/locking/lockdep.c:5879
 rcu_lock_release include/linux/rcupdate.h:322 [inline]
 rcu_read_unlock include/linux/rcupdate.h:881 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
 unwind_next_frame+0x1aaa/0x23c0 arch/x86/kernel/unwind_orc.c:695
 __unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:773
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24
 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
 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:2692 [inline]
 slab_free mm/slub.c:6168 [inline]
 kmem_cache_free+0x187/0x630 mm/slub.c:6298
 skb_kfree_head net/core/skbuff.c:1087 [inline]
 skb_free_head net/core/skbuff.c:1101 [inline]
 skb_release_data+0x6c3/0x940 net/core/skbuff.c:1128
 skb_release_all net/core/skbuff.c:1203 [inline]
 __kfree_skb+0x5d/0x210 net/core/skbuff.c:1217
 tcp_write_queue_purge+0x143/0x360 net/ipv4/tcp.c:3391
 tcp_done_with_error+0x43/0xd0 net/ipv4/tcp_input.c:4896
 tcp_write_err net/ipv4/tcp_timer.c:78 [inline]
 tcp_write_timeout net/ipv4/tcp_timer.c:295 [inline]
 tcp_retransmit_timer+0x1f0e/0x35f0 net/ipv4/tcp_timer.c:603
 tcp_write_timer+0x15c/0x2d0 net/ipv4/tcp_timer.c:739
 call_timer_fn+0x192/0x640 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2373 [inline]
 __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385
 run_timer_base kernel/time/timer.c:2394 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404
 handle_softirqs+0x22a/0x870 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__schedule+0x0/0x52d0 kernel/sched/core.c:6762
Code: 81 f6 45 89 f8 89 d9 48 8b 5c 24 08 e9 ee fe ff ff cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48
RSP: 0018:ffffc9000c3cf688 EFLAGS: 00000206
RAX: 000000000004b569 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8def4b65 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffffffff90118bb7 R09: 1ffffffff2023176
R10: dffffc0000000000 R11: fffffbfff2023177 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7235
 irqentry_exit+0x599/0x620 kernel/entry/common.c:239
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872
Code: e9 30 ff ff ff e8 35 59 0c 0a f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 b1 46 7a 11 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 16 3f 0f 0a cc 48 8d 3d 3e 55 73
RSP: 0018:ffffc9000c3cf7b8 EFLAGS: 00000286
RAX: 3d0a075feab22300 RBX: 0000000000000246 RCX: 0000000000000046
RDX: 000000005a44979c RSI: ffffffff8e1655c0 RDI: ffffffff8c27b380
RBP: 0000000000000000 R08: ffffffff81767de5 R09: ffffffff8e75e3e0
R10: dffffc0000000000 R11: ffffffff81b0bfa0 R12: 0000000000000002
R13: ffffffff8e75e3e0 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
 rcu_read_lock include/linux/rcupdate.h:850 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
 unwind_next_frame+0xc2/0x23c0 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:5263 [inline]
 __kmalloc_noprof+0x35c/0x760 mm/slub.c:5275
 kmalloc_noprof include/linux/slab.h:954 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 lsm_blob_alloc security/security.c:192 [inline]
 lsm_sock_alloc security/security.c:4375 [inline]
 security_sk_alloc+0x52/0x360 security/security.c:4391
 sk_prot_alloc+0x101/0x210 net/core/sock.c:2248
 sk_alloc+0x3a/0x390 net/core/sock.c:2301
 inet6_create+0x7f0/0x1260 net/ipv6/af_inet6.c:193
 __sock_create+0x4b2/0x9d0 net/socket.c:1605
 sock_create net/socket.c:1663 [inline]
 __sys_socket_create net/socket.c:1700 [inline]
 __sys_socket+0xd6/0x1b0 net/socket.c:1747
 __do_sys_socket net/socket.c:1761 [inline]
 __se_sys_socket net/socket.c:1759 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1759
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f46fd99c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f46fe777028 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00007f46fdc15fa0 RCX: 00007f46fd99c799
RDX: 0000000000000106 RSI: 0000000000000001 RDI: 000000000000000a
RBP: 00007f46fda32c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f46fdc16038 R14: 00007f46fdc15fa0 R15: 00007ffe8475e0d8
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 13949 Comm: kworker/u9:5 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026
Workqueue: hci0 hci_cmd_timeout
RIP: 0010:timekeeping_cycles_to_ns kernel/time/timekeeping.c:399 [inline]
RIP: 0010:timekeeping_get_ns kernel/time/timekeeping.c:404 [inline]
RIP: 0010:ktime_get_update_offsets_now+0x11f/0x3d0 kernel/time/timekeeping.c:2573
Code: df 80 3c 08 00 74 08 48 89 ef e8 ec a8 7c 00 49 21 dd 48 8b 6d 00 4c 89 ef 48 89 ee e8 1a 61 12 00 49 39 ed 0f 87 64 01 00 00 <8b> 05 4b 36 78 18 4c 0f af e8 4c 03 2d 48 36 78 18 8b 2d 3e 36 78
RSP: 0018:ffffc90000a08e20 EFLAGS: 00000097
RAX: ffffffff81b33ef6 RBX: ffffffffffffffff RCX: ffff88802c5b9e80
RDX: 0000000000010000 RSI: 000001fb63109b96 RDI: 000000000369ba32
RBP: 000001fb63109b96 R08: ffffffff81b33e47 R09: ffffffff9a2b7508
R10: dffffc0000000000 R11: ffffffff816b26b0 R12: 0000019f5c0aed7c
R13: 000000000369ba32 R14: ffff8880b87284e0 R15: 00000000000541b2
FS:  0000000000000000(0000) GS:ffff888125563000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa980deb4b8 CR3: 0000000063b1e000 CR4: 00000000003526f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 hrtimer_update_base kernel/time/hrtimer.c:641 [inline]
 hrtimer_interrupt+0x132/0x1010 kernel/time/hrtimer.c:1893
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x460 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline]
RIP: 0010:vprintk_emit+0x45d/0x560 kernel/printk/printk.c:2478
Code: 0f 84 44 ff ff ff e8 42 2d 21 00 fb eb 44 e8 3a 2d 21 00 e8 15 72 09 0a 4d 85 f6 74 94 e8 2b 2d 21 00 fb 48 c7 c7 20 08 75 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 cb 16
RSP: 0018:ffffc9000c9d7800 EFLAGS: 00000293
RAX: ffffffff81a47085 RBX: ffffffff81a46eff RCX: ffff88802c5b9e80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e750820
RBP: ffffc9000c9d78b0 R08: ffffffff90118bb7 R09: 1ffffffff2023176
R10: dffffc0000000000 R11: fffffbfff2023177 R12: 0000000000000000
R13: 000000000000002a R14: 0000000000000200 R15: 1ffff9200193af04
 _printk+0xdd/0x130 kernel/printk/printk.c:2504
 bt_err+0x121/0x180 net/bluetooth/lib.c:296
 hci_cmd_timeout+0xd8/0x1e0 net/bluetooth/hci_core.c:1470
 process_one_work kernel/workqueue.c:3275 [inline]
 process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358
 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>