INFO: task syz.4.6734:29697 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc4-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.6734      state:D stack:22408 pid:29697 tgid:29697 ppid:27996  task_flags:0x400040 flags:0x00004006
Call Trace:
 <TASK>
 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
 request_wait_answer fs/fuse/dev.c:565 [inline]
 __fuse_request_send fs/fuse/dev.c:579 [inline]
 __fuse_simple_request+0xf15/0x18d0 fs/fuse/dev.c:673
 fuse_simple_request fs/fuse/fuse_i.h:1237 [inline]
 fuse_flush+0x5d4/0x800 fs/fuse/file.c:475
 filp_flush+0xbd/0x190 fs/open.c:1549
 filp_close+0x1d/0x40 fs/open.c:1562
 __range_close fs/file.c:752 [inline]
 __do_sys_close_range fs/file.c:811 [inline]
 __se_sys_close_range+0x359/0x650 fs/file.c:775
 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: 0033:0x7fc3cf58e929
RSP: 002b:00007ffd7648cea8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007fc3cf7b7ba0 RCX: 00007fc3cf58e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fc3cf7b7ba0 R08: 00000000000001fc R09: 0000001e7648d19f
R10: 00007fc3cf7b7ac0 R11: 0000000000000246 R12: 00000000001edbf6
R13: 00007fc3cf7b6320 R14: ffffffffffffffff R15: 00007ffd7648cfc0
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5585:
 #0: ffff88814c8ff0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by kworker/u8:16/6888:
1 lock held by syz-executor/25875:
 #0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
 #0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc4-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 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+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-rc4-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: c3 dd 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 63 55 28 00 f3 0f 1e fa fb f4 <e9> 98 dd 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2
RAX: be38408487e94700 RBX: ffffffff81974c88 RCX: be38408487e94700
RDX: 0000000000000001 RSI: ffffffff8d96e743 RDI: ffffffff8be1b900
RBP: ffffc90000197f20 R08: ffff8880b8732f5b R09: 1ffff110170e65eb
R10: dffffc0000000000 R11: ffffed10170e65ec R12: ffffffff8f9fdaf0
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003a5eb40
FS:  0000000000000000(0000) GS:ffff888125d84000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000028000 CR3: 000000005a088000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000001889
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:749
 default_idle_call+0x74/0xb0 kernel/sched/idle.c:117
 cpuidle_idle_call kernel/sched/idle.c:185 [inline]
 do_idle+0x1e8/0x510 kernel/sched/idle.c:325
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x147
 </TASK>