INFO: task syz-executor:7360 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:22376 pid:7360 tgid:7360 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1821/0x5740 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7f7/0x1550 kernel/locking/mutex.c:820
del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:234
kernfs_fop_write_iter+0x3af/0x540 fs/kernfs/file.c:352
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x61d/0xb90 fs/read_write.c:688
ksys_write+0x150/0x270 fs/read_write.c:740
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9a31d5d68e
RSP: 002b:00007f9a3213f1e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000555566e66500 RCX: 00007f9a31d5d68e
RDX: 0000000000000001 RSI: 00007f9a3213f270 RDI: 0000000000000005
RBP: 00007f9a31e335f2 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007f9a3213f270 R14: 00007f9a32b44620 R15: 0000000000000003
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e95cce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e95cce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e95cce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:2/35:
#0: ffff88801be8e140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#0: ffff88801be8e140 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
#1: ffffc90000ab7c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
#1: ffffc90000ab7c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
#2: ffffffff8fdc2d68 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673
#3: ffffffff8e962eb8 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
2 locks held by getty/5382:
#0: ffff8880372010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
4 locks held by kworker/1:6/5718:
2 locks held by kworker/0:7/5793:
4 locks held by kworker/1:9/9092:
3 locks held by kworker/u8:14/27503:
#0: ffff88801ae84140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
#0: ffff88801ae84140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
#1: ffffc900058ffc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
#1: ffffc900058ffc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
#2: ffffffff8fdd1a40 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
8 locks held by syz-executor/6406:
#0: ffff88803641e410 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2724 [inline]
#0: ffff88803641e410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90 fs/read_write.c:684
#1: ffff88806de44080 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540 fs/kernfs/file.c:343
#2: ffff888029c77788 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888029c77788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540 fs/kernfs/file.c:344
#3: ffffffff8f650740 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:234
#4: ffff88803a117128 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline]
#4: ffff88803a117128 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1174 [inline]
#4: ffff88803a117128 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x870 drivers/base/dd.c:1372
#5: ffff88803a110258 (&devlink->lock_key#33){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x170 drivers/net/netdevsim/dev.c:1799
#6: ffffffff8fdd1a40 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x16b/0x7f0 drivers/net/netdevsim/netdev.c:1188
#7: ffffffff8e962fe8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#7: ffffffff8e962fe8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
4 locks held by syz-executor/7360:
#0: ffff88803641e410 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2724 [inline]
#0: ffff88803641e410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90 fs/read_write.c:684
#1: ffff88803247a080 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540 fs/kernfs/file.c:343
#2: ffff888029c77788 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888029c77788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540 fs/kernfs/file.c:344
#3: ffffffff8f650740 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:234
3 locks held by syz-executor/7813:
#0: ffff888083d8cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff888083d8cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff888083d8c0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5359
#2: ffffffff8ff551e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff8ff551e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2734
3 locks held by syz-executor/7816:
#0: ffff8880398bcea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff8880398bcea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff8880398bc0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5359
#2: ffffffff8ff551e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff8ff551e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2734
5 locks held by syz-executor/7819:
#0: ffff88806e08cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff88806e08cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff88806e08c0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5359
#2: ffffffff8ff551e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff8ff551e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2734
#3: ffff88807a8112f8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x92/0x570 net/bluetooth/l2cap_core.c:1777
#4: ffffffff8e962fe8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#4: ffffffff8e962fe8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
3 locks held by syz-executor/7825:
#0: ffff888050d30ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff888050d30ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff888050d300b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5359
#2: ffffffff8ff551e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff8ff551e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2734
3 locks held by syz-executor/7831:
#0: ffff88806df7cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline]
#0: ffff88806df7cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716
#1: ffff88806df7c0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5359
#2: ffffffff8ff551e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff8ff551e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2734
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
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
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 114 Comm: kworker/u8:5 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:skb_end_pointer include/linux/skbuff.h:1724 [inline]
RIP: 0010:__dev_queue_xmit+0x210/0x3950 net/core/dev.c:4778
Code: 6c 24 20 4d 89 e7 0f 84 e1 1e 00 00 e8 d9 f0 47 f8 49 bd 00 00 00 00 00 fc ff df 48 89 5c 24 40 48 8b 44 24 50 42 80 3c 28 00 <74> 08 4c 89 ff e8 76 35 b3 f8 48 8b 44 24 08 48 8b 98 d0 00 00 00
RSP: 0018:ffffc90000a07ee0 EFLAGS: 00000246
RAX: 1ffff110078e6f82 RBX: ffff88803c737bb0 RCX: ffff88801e328000
RDX: 0000000000000100 RSI: 0000000000000036 RDI: 0000000000000000
RBP: ffffc90000a08190 R08: 0aaaaaaaaaaa0000 R09: 00080aaaaaaaaaaa
R10: 0aaaaaaaaaaa0000 R11: 00080aaaaaaaaaaa R12: ffff88803c737c10
R13: dffffc0000000000 R14: 0000000000000036 R15: ffff88803c737c10
FS: 0000000000000000(0000) GS:ffff888125387000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f80a3e25000 CR3: 000000000e74a000 CR4: 00000000003526f0
Call Trace:
dev_queue_xmit include/linux/netdevice.h:3418 [inline]
neigh_hh_output include/net/neighbour.h:544 [inline]
neigh_output include/net/neighbour.h:558 [inline]
ip_finish_output2+0xc68/0x1070 net/ipv4/ip_output.c:237
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip_output+0x29f/0x450 net/ipv4/ip_output.c:438
synproxy_send_client_synack+0x8c1/0xe30 net/netfilter/nf_synproxy_core.c:485
nft_synproxy_eval_v4+0x34a/0x4e0 net/netfilter/nft_synproxy.c:60
nft_synproxy_do_eval+0x305/0x580 net/netfilter/nft_synproxy.c:142
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x48d/0x1ae0 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x360/0x4b0 net/netfilter/nft_chain_filter.c:162
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
nf_hook include/linux/netfilter.h:273 [inline]
NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:316
NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6202 [inline]
__netif_receive_skb net/core/dev.c:6315 [inline]
process_backlog+0xaa3/0x1950 net/core/dev.c:6666
__napi_poll+0xae/0x340 net/core/dev.c:7733
napi_poll net/core/dev.c:7796 [inline]
net_rx_action+0x627/0xf70 net/core/dev.c:7953
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:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfcf/0x13d0 kernel/smp.c:892
Code: 79 45 8b 2e 44 89 ee 83 e6 01 31 ff e8 9a 07 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 45 03 0c 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 2a 03 0c
RSP: 0018:ffffc900025d7700 EFLAGS: 00000293
RAX: ffffffff81b9b2d6 RBX: ffff8880b873c148 RCX: ffff88801e328000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900025d7840 R08: ffffffff9030dbf7 R09: 1ffffffff2061b7e
R10: dffffc0000000000 R11: fffffbfff2061b7f R12: 1ffff110170c8589
R13: dffffc0000000000 R14: ffff8880b8642c48 R15: 0000000000000000
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
smp_text_poke_batch_finish+0xb5f/0x1160 arch/x86/kernel/alternative.c:3045
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:240
static_key_disable+0x1a/0x20 kernel/jump_label.c:248
toggle_allocation_gate+0x1fe/0x290 mm/kfence/core.c:913
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