INFO: task syz.0.18:4383 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.18 state:D stack:28256 pid: 4383 ppid: 4309 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0x97/0x280 kernel/time/timer.c:1890 do_wait_for_common+0x29a/0x440 kernel/sched/completion.c:85 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x48/0x60 kernel/sched/completion.c:138 kthread_stop+0x16e/0x540 kernel/kthread.c:666 f2fs_stop_gc_thread+0x61/0xa0 fs/f2fs/gc.c:186 f2fs_ioc_shutdown fs/f2fs/file.c:2308 [inline] __f2fs_ioctl+0x6732/0xc370 fs/f2fs/file.c:4221 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fa3b72366c9 RSP: 002b:00007fa3b6884038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa3b748d090 RCX: 00007fa3b72366c9 RDX: 0000200000000080 RSI: 000000008004587d RDI: 0000000000000004 RBP: 00007fa3b72b8f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa3b748d128 R14: 00007fa3b748d090 R15: 00007ffd800bb438 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/u4:4/3058: #0: ffff8880b903a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 #1: ffff8880b9027888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x495/0x810 kernel/sched/psi.c:882 2 locks held by getty/3948: #0: ffff88814d01c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 1 lock held by syz.0.18/4383: #0: ffff88807ac5c460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:430 1 lock held by syz.1.22/4436: #0: ffff88807401a460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:430 1 lock held by syz.2.23/4463: #0: ffff8880282b6460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:430 1 lock held by syz.3.25/4493: #0: ffff88802a320460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:430 1 lock held by syz.4.26/4526: #0: ffff88801f42a460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:430 1 lock held by syz.5.27/4571: #0: ffff88804a9a4460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:430 1 lock held by syz.6.36/4659: #0: ffff88802d6e4460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:430 1 lock held by syz.7.40/4714: #0: ffff888077442460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write_file+0x5c/0x200 fs/namespace.c:430 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4332 Comm: kworker/0:11 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:lock_is_held_type+0x1/0x190 kernel/locking/lockdep.c:5651 Code: c0 03 00 75 d6 48 c7 c7 00 1b 0b 8a 48 c7 c6 40 1b 0b 8a e8 c1 37 f5 ff 0f 0b eb bf e8 98 fd ff ff 0f 1f 84 00 00 00 00 00 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 RSP: 0018:ffffc900031ffba8 EFLAGS: 00000202 RAX: ffffffff87dab0f7 RBX: 0000000000000001 RCX: ffff88802b528000 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8d3381f0 RBP: 0000000000000000 R08: 0000000000000004 R09: 0000000000000003 R10: fffff5200063ff68 R11: 1ffff9200063ff68 R12: ffff888077402c08 R13: dffffc0000000000 R14: 000000000000000a R15: 0000000100000040 FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561c5dfd4168 CR3: 00000000299d9000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:287 [inline] neigh_periodic_work+0x42a/0xc70 net/core/neighbour.c:921 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287