INFO: task syz.3.110:7085 blocked for more than 143 seconds.
Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.110 state:D stack:28904 pid:7085 tgid:7071 ppid:5825 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write_nested+0x1b5/0x200 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:914 [inline]
filename_create+0x1f9/0x470 fs/namei.c:4148
do_mkdirat+0xa0/0x590 fs/namei.c:4400
__do_sys_mkdirat fs/namei.c:4425 [inline]
__se_sys_mkdirat fs/namei.c:4423 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4423
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6d3b78d197
RSP: 002b:00007f6d3c615e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f6d3c615ef0 RCX: 00007f6d3b78d197
RDX: 00000000000001ff RSI: 0000200000000280 RDI: 00000000ffffff9c
RBP: 00002000000002c0 R08: 00002000000007c0 R09: 0000000000000000
R10: 00002000000002c0 R11: 0000000000000246 R12: 0000200000000280
R13: 00007f6d3c615eb0 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
#0: ffff88814c601148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88814c601148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90000127bc0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000127bc0 ((work_completion)(&peer->transmit_handshake_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#2: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#2: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
#2: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: batadv_nc_worker+0xd2/0x610 net/batman-adv/network-coding.c:719
3 locks held by kworker/1:0/24:
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc900001e7bc0 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900001e7bc0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#2: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
1 lock held by khungtaskd/31:
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
3 locks held by kworker/0:3/980:
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90003807bc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003807bc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff888051aba240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490
2 locks held by getty/5590:
#0: ffff88814c61c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fee2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/0:5/5904:
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000496fbc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000496fbc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff88807bb48240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490
1 lock held by syz-executor/6086:
#0: ffff8880680c20e0 (&type->s_umount_key#100){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff8880680c20e0 (&type->s_umount_key#100){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff8880680c20e0 (&type->s_umount_key#100){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
4 locks held by kworker/u8:10/6778:
#0: ffff88801ead2948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801ead2948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000494fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000494fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff8880335ea0e0 (&type->s_umount_key#100){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff888057155df8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
1 lock held by dhcpcd/7011:
#0: ffff88807d505c08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#0: ffff88807d505c08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline]
#0: ffff88807d505c08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1391
5 locks held by syz.3.110/7072:
2 locks held by syz.3.110/7085:
#0: ffff8880335ea428 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff888057150eb0 (&type->i_mutex_dir_key#18/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#1: ffff888057150eb0 (&type->i_mutex_dir_key#18/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4148
2 locks held by syz.0.143/7412:
#0: ffff8880335ea0e0 (&type->s_umount_key#100){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff8880335ea0e0 (&type->s_umount_key#100){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
#1: ffff888024dc27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff888024dc27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
2 locks held by syz.1.145/7443:
#0: ffff8880335ea0e0 (&type->s_umount_key#100){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff8880335ea0e0 (&type->s_umount_key#100){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
#1: ffff888024dc27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff888024dc27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
2 locks held by syz.1.145/7444:
#0: ffff8880335ea0e0 (&type->s_umount_key#100){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff8880335ea0e0 (&type->s_umount_key#100){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
#1: ffff888024dc27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff888024dc27d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
1 lock held by syz-executor/8796:
#0: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
4 locks held by syz.5.290/9077:
#0: ffff88807c294d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline]
#0: ffff88807c294d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2691
#1: ffff88807c294078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5238
#2: ffffffff8f666068 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2066 [inline]
#2: ffffffff8f666068 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2560
#3: ffff88802766db38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762
2 locks held by sed/9130:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
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: 12 Comm: kworker/u8:0 Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:__find_rr_leaf+0x12d/0x6d0 net/ipv6/route.c:838
Code: 44 24 68 4c 89 7c 24 30 4d 85 ff 74 3c 49 8d 9e 90 00 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 7e 03 00 00 8b 1b <89> df 44 8b 64 24 44 44 89 e6 e8 04 72 a9 f7 44 39 e3 0f 85 07 04
RSP: 0018:ffffc90000a08220 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000100 RCX: ffff88801d28da00
RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000a08378 R08: ffffc90000a084a0 R09: ffffc90000a084b0
R10: ffffc90000a08300 R11: fffff52000141062 R12: 1ffff1100efcfd0c
R13: dffffc0000000000 R14: ffff8880540f1c00 R15: ffffc90000a08478
FS: 0000000000000000(0000) GS:ffff888125d85000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556738ece950 CR3: 0000000029bce000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
find_rr_leaf net/ipv6/route.c:890 [inline]
rt6_select net/ipv6/route.c:934 [inline]
fib6_table_lookup+0x39f/0xa80 net/ipv6/route.c:2232
ip6_pol_route+0x222/0x1180 net/ipv6/route.c:2268
pol_lookup_func include/net/ip6_fib.h:617 [inline]
fib6_rule_lookup+0x52f/0x6f0 net/ipv6/fib6_rules.c:120
ip6_route_input_lookup net/ipv6/route.c:2337 [inline]
ip6_route_input+0x6ce/0xa50 net/ipv6/route.c:2640
ip6_rcv_finish+0x141/0x2d0 net/ipv6/ip6_input.c:77
NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:317
__netif_receive_skb_one_core net/core/dev.c:5977 [inline]
__netif_receive_skb+0xd3/0x380 net/core/dev.c:6090
process_backlog+0x60e/0x14f0 net/core/dev.c:6442
__napi_poll+0xc7/0x480 net/core/dev.c:7414
napi_poll net/core/dev.c:7478 [inline]
net_rx_action+0x707/0xe30 net/core/dev.c:7605
handle_softirqs+0x286/0x870 kernel/softirq.c:579
do_softirq+0xec/0x180 kernel/softirq.c:480
__local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:910 [inline]
__dev_queue_xmit+0x1cd7/0x3a70 net/core/dev.c:4740
dev_queue_xmit include/linux/netdevice.h:3355 [inline]
neigh_hh_output include/net/neighbour.h:523 [inline]
neigh_output include/net/neighbour.h:537 [inline]
ip6_finish_output2+0x11bc/0x16a0 net/ipv6/ip6_output.c:141
__ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]
ip6_finish_output+0x234/0x7d0 net/ipv6/ip6_output.c:226
NF_HOOK+0x9e/0x380 include/linux/netfilter.h:317
mld_sendpack+0x800/0xd80 net/ipv6/mcast.c:1868
ipv6_mc_dad_complete+0x88/0x4b0 net/ipv6/mcast.c:2293
addrconf_dad_completed+0x6d5/0xd60 net/ipv6/addrconf.c:4344
addrconf_dad_work+0xc36/0x14b0 net/ipv6/addrconf.c:-1
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245