INFO: task syz.3.19991:18554 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.19991     state:D stack:23256 pid:18554 tgid:18554 ppid:5638   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 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
 svc_disconnect+0x231/0x460 net/atm/svc.c:65
 svc_release+0x64/0xd0 net/atm/svc.c:95
 __sock_release net/socket.c:722 [inline]
 sock_close+0xc3/0x240 net/socket.c:1514
 __fput+0x44f/0xa60 fs/file_table.c:510
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
 exit_to_user_mode_loop+0x193/0x680 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f15b319ce59
RSP: 002b:00007ffdc8f7fe28 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f15b3417da0 RCX: 00007f15b319ce59
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f15b3417da0 R08: 00007f15b3416128 R09: 0000000000000000
R10: 00000000005edf14 R11: 0000000000000246 R12: 0000000000108128
R13: 00007f15b3415fac R14: 0000000000107eaa R15: 00007f15b3415fa0
 </TASK>

Showing all locks held in the system:
2 locks held by ksoftirqd/0/15:
1 lock held by khungtaskd/31:
 #0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5392:
 #0: ffff8880328da0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
1 lock held by syz.3.19991/18554:
 #0: ffff888056410240 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline]
 #0: ffff888056410240 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release net/socket.c:721 [inline]
 #0: ffff888056410240 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1514
2 locks held by syz.2.19996/18569:
2 locks held by syz.4.20498/20935:
 #0: ffffffff8fdba228 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x4f7/0x730 net/core/net_namespace.c:575
 #1: ffff88807d128fe0 (&device->compat_devs_mutex){+.+.}-{4:4}, at: remove_one_compat_dev drivers/infiniband/core/device.c:1007 [inline]
 #1: ffff88807d128fe0 (&device->compat_devs_mutex){+.+.}-{4:4}, at: rdma_dev_exit_net+0x1b2/0x350 drivers/infiniband/core/device.c:1149
1 lock held by syz.5.20503/20954:
 #0: ffffffff8e962fa8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
 #0: ffffffff8e962fa8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
5 locks held by syz.0.20509/20991:
2 locks held by syz.8.20515/21018:
 #0: ffffffff8fdc8f40 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:641 [inline]
 #0: ffffffff8fdc8f40 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3505
 #1: ffffffff8e962fa8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
 #1: ffffffff8e962fa8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
2 locks held by dhcpcd-run-hook/21032:

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17234 Comm: kworker/0:15 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events free_ipc
RIP: 0010:__bfs_next kernel/locking/lockdep.c:1702 [inline]
RIP: 0010:__bfs kernel/locking/lockdep.c:1752 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x17c0/0x2cf0 kernel/locking/lockdep.c:5237
Code: 05 c5 f8 9f 14 31 ff 45 31 e4 4d 85 e4 4c 8b 6c 24 10 74 30 49 8b 44 24 30 48 85 c0 74 26 48 8b 40 10 48 83 c0 30 49 8b 0c 24 <48> 89 8c 24 d8 00 00 00 48 39 c1 74 0d 4c 8b a4 24 d8 00 00 00 4d
RSP: 0018:ffffc90005b0f480 EFLAGS: 00000082
RAX: ffffffff93e28b20 RBX: 00000000000003fd RCX: ffffffff96d87508
RDX: ffffffff96d74c68 RSI: ffff888057b0ca58 RDI: 00000000000003fd
RBP: 29c9c61561faf703 R08: ffffc90005b0f448 R09: 0000000000000020
R10: 0000000000000003 R11: ffffffff81a21250 R12: ffffffff96d873b8
R13: ffff888057b0ca58 R14: ffff888057b0be00 R15: 000000000000020c
FS:  0000000000000000(0000) GS:ffff88812528a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005622132a3950 CR3: 000000000e74a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
 seqcount_lockdep_reader_access+0x55/0x100 include/linux/seqlock.h:73
 ktime_get+0x45/0x220 kernel/time/timekeeping.c:965
 clockevents_program_event+0x290/0x630 kernel/time/clockevents.c:363
 hrtimer_rearm kernel/time/hrtimer.c:2039 [inline]
 __hrtimer_rearm_deferred+0x270/0x450 kernel/time/hrtimer.c:2059
 hrtimer_rearm_deferred_tif include/linux/hrtimer_rearm.h:53 [inline]
 hrtimer_rearm_deferred include/linux/hrtimer_rearm.h:62 [inline]
 irqentry_exit_to_kernel_mode_after_preempt include/linux/irq-entry-common.h:505 [inline]
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:542 [inline]
 irqentry_exit+0x875/0x8b0 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__hlist_del include/linux/list.h:1031 [inline]
RIP: 0010:hlist_del_init_rcu include/linux/rculist.h:238 [inline]
RIP: 0010:proc_invalidate_siblings_dcache+0x1a0/0x6c0 fs/proc/inode.c:120
Code: 06 1b c5 ff 49 89 1f 48 85 db 74 34 e8 c9 c3 59 ff 48 83 c3 08 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 48 89 df e8 d6 1a c5 ff 4c 89 3b eb 0c e8 9c c3 59 ff eb 26
RSP: 0018:ffffc90005b0f8c8 EFLAGS: 00000246
RAX: 1ffff1100b11a5b0 RBX: ffff8880588d2d80 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffc90005b0f840
RBP: ffff8880588d0540 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000b61f08 R12: 1ffff1100b11a0a8
R13: ffff8880588d0538 R14: ffff888034c68000 R15: ffff88807fb8e848
 proc_sys_invalidate_dcache fs/proc/proc_sysctl.c:289 [inline]
 start_unregistering fs/proc/proc_sysctl.c:316 [inline]
 drop_sysctl_table+0x20b/0x5e0 fs/proc/proc_sysctl.c:1517
 unregister_sysctl_table+0x41/0x60 fs/proc/proc_sysctl.c:1542
 retire_ipc_sysctls+0x5e/0x80 ipc/ipc_sysctl.c:310
 free_ipc_ns ipc/namespace.c:162 [inline]
 free_ipc+0x12e/0x1d0 ipc/namespace.c:183
 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
 </TASK>