INFO: task syz-executor:7687 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21704 pid:7687 ppid:1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
wb_wait_for_completion+0x173/0x2a0 fs/fs-writeback.c:192
sync_inodes_sb+0x1c9/0xa10 fs/fs-writeback.c:2778
sync_filesystem+0x171/0x220 fs/sync.c:64
generic_shutdown_super+0x6f/0x2b0 fs/super.c:666
kill_block_super+0x44/0x90 fs/super.c:1660
deactivate_locked_super+0x97/0x100 fs/super.c:481
cleanup_mnt+0x43b/0x4d0 fs/namespace.c:1259
task_work_run+0x1d4/0x260 kernel/task_work.c:245
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x95a/0x2460 kernel/exit.c:883
do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
__do_sys_exit_group kernel/exit.c:1035 [inline]
__se_sys_exit_group kernel/exit.c:1033 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0a19f9bf79
RSP: 002b:00007ffc8b2cfb88 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f0a1a031c9b RCX: 00007f0a19f9bf79
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 000000000000000c R08: 0000000000000000 R09: 00007f0a1a031c3b
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc8b2d0e40
R13: 00007f0a1a031c3b R14: 0000555577b3c4e8 R15: 00007ffc8b2d1f10
Showing all locks held in the system:
3 locks held by kworker/0:1/9:
#0: ffff8880b8e3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa9/0x140 kernel/sched/core.c:567
#1: ffff8880b8e289c0 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffff8880b8e289c0 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2176/0x45a0 kernel/sched/core.c:6695
#2: ffffffff8d2140e8 (vmap_purge_lock){+.+.}-{3:3}, at: drain_vmap_area_work+0x32/0xd0 mm/vmalloc.c:1811
2 locks held by kworker/u4:1/12:
1 lock held by khungtaskd/29:
#0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d131fe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
3 locks held by kworker/u4:5/1072:
1 lock held by dhcpcd/5432:
#0: ffff8880b8e3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa9/0x140 kernel/sched/core.c:567
2 locks held by getty/5526:
#0: ffff88802d8a70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x433/0x1390 drivers/tty/n_tty.c:2217
1 lock held by syz.1.433/7615:
2 locks held by syz-executor/7687:
#0: ffff88802ed600e0 (&type->s_umount_key#114){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88802ed600e0 (&type->s_umount_key#114){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88802ed600e0 (&type->s_umount_key#114){+.+.}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513
#1: ffff888021c707d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:364 [inline]
#1: ffff888021c707d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1ad/0xa10 fs/fs-writeback.c:2776
1 lock held by syz-executor/8853:
#0: ffffffff8e3c0188 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8e3c0188 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3511
1 lock held by syz-executor/9857:
5 locks held by syz.6.1021/10560:
#0: ffff88807ba34e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:521 [inline]
#0: ffff88807ba34e70 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x212/0x500 net/bluetooth/hci_core.c:2709
#1: ffff88807ba340b8 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x4c9/0xfa0 net/bluetooth/hci_sync.c:5273
#2: ffffffff8e52d728 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2011 [inline]
#2: ffffffff8e52d728 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa1/0x220 net/bluetooth/hci_conn.c:2540
#3: ffff88802f6ccb38 (&conn->lock#2){+.+.}-{3:3}, at: l2cap_conn_del+0x70/0x660 net/bluetooth/l2cap_core.c:1763
#4: ffffffff8d1379b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#4: ffffffff8d1379b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
2 locks held by dhcpcd/10573:
#0: ffff888079e04130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#0: ffff888079e04130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcc0 net/packet/af_packet.c:3258
#1: ffffffff8d1379b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
#1: ffffffff8d1379b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x306/0x880 kernel/rcu/tree_exp.h:1004
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf3d/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6228 Comm: kworker/u4:11 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__rcu_read_unlock+0x62/0xd0 kernel/rcu/tree_plugin.h:431
Code: 75 1d 4c 8d b7 40 04 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 75 5f 41 83 3e 00 75 20 43 0f b6 04 3c 84 c0 75 3a 8b 03 <3d> 00 00 00 40 73 0a 5b 41 5c 41 5d 41 5e 41 5f c3 0f 0b eb f2 e8
RSP: 0018:ffffc90004157b30 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888023f7c03c RCX: ffff888023f7bc00
RDX: 0000000000000000 RSI: ffffffff8b1c81c0 RDI: ffff888023f7bc00
RBP: fffffffffffffe38 R08: dffffc0000000000 R09: 1ffffffff2237ea0
R10: dffffc0000000000 R11: fffffbfff2237ea1 R12: 1ffff110047ef807
R13: ffffffff8a4bcb32 R14: ffff888023f7c040 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd6adf0d74 CR3: 00000000192d6000 CR4: 00000000003506e0
Call Trace:
rcu_read_unlock include/linux/rcupdate.h:818 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
batadv_nc_worker+0x282/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293