rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: {
 0-...D
 } 2664 jiffies s: 81265 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):

Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 2535 Comm: acpid Not tainted 6.12.0-rc4-syzkaller-00052-gc6d9e43954bf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:407
Code: 68 b5 fe 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c c3 cc cc cc cc e8 78 ef 0d ff eb a2 e8 01 f0
RSP: 0018:ffffc90000006f00 EFLAGS: 00000002
RAX: dffffc0000000060 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff82a08a30 RDI: ffffffff93637660
RBP: ffffffff93637620 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff26c6f1e R15: dffffc0000000000
FS:  00007f379b72d740(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c383a75 CR3: 0000000115ebc000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 serial_in drivers/tty/serial/8250/8250.h:137 [inline]
 serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
 wait_for_lsr+0xda/0x180 drivers/tty/serial/8250/8250_port.c:2068
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3315 [inline]
 serial8250_console_write+0xf5a/0x17c0 drivers/tty/serial/8250/8250_port.c:3393
 console_emit_next_record kernel/printk/printk.c:3092 [inline]
 console_flush_all+0x800/0xc60 kernel/printk/printk.c:3180
 __console_flush_and_unlock kernel/printk/printk.c:3239 [inline]
 console_unlock+0xd9/0x210 kernel/printk/printk.c:3279
 vprintk_emit+0x424/0x6f0 kernel/printk/printk.c:2407
 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:68
 _printk+0xc8/0x100 kernel/printk/printk.c:2432
 printk_stack_address arch/x86/kernel/dumpstack.c:72 [inline]
 show_trace_log_lvl+0x1b7/0x3d0 arch/x86/kernel/dumpstack.c:285
 sched_show_task kernel/sched/core.c:7604 [inline]
 sched_show_task+0x3f0/0x5f0 kernel/sched/core.c:7579
 show_state_filter+0xee/0x320 kernel/sched/core.c:7649
 k_spec drivers/tty/vt/keyboard.c:667 [inline]
 k_spec+0xed/0x150 drivers/tty/vt/keyboard.c:656
 kbd_keycode drivers/tty/vt/keyboard.c:1522 [inline]
 kbd_event+0xcbd/0x17a0 drivers/tty/vt/keyboard.c:1541
 input_handler_events_default+0x116/0x1b0 drivers/input/input.c:2549
 input_pass_values+0x777/0x8e0 drivers/input/input.c:126
 input_event_dispose drivers/input/input.c:352 [inline]
 input_handle_event+0xb30/0x14d0 drivers/input/input.c:369
 input_event drivers/input/input.c:398 [inline]
 input_event+0x83/0xa0 drivers/input/input.c:390
 hidinput_hid_event+0xa12/0x2410 drivers/hid/hid-input.c:1719
 hid_process_event+0x4b7/0x5e0 drivers/hid/hid-core.c:1540
 hid_input_array_field+0x330/0x710 drivers/hid/hid-core.c:1644
 hid_process_report drivers/hid/hid-core.c:1694 [inline]
 hid_report_raw_event+0xa02/0x11c0 drivers/hid/hid-core.c:2040
 __hid_input_report.constprop.0+0x341/0x440 drivers/hid/hid-core.c:2110
 hid_irq_in+0x35e/0x870 drivers/hid/usbhid/hid-core.c:285
 __usb_hcd_giveback_urb+0x389/0x6e0 drivers/usb/core/hcd.c:1650
 usb_hcd_giveback_urb+0x396/0x450 drivers/usb/core/hcd.c:1734
 dummy_timer+0x17f0/0x3930 drivers/usb/gadget/udc/dummy_hcd.c:1993
 __run_hrtimer kernel/time/hrtimer.c:1691 [inline]
 __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1755
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1772
 handle_softirqs+0x206/0x8d0 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0xac/0x110 kernel/softirq.c:649
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:raw_atomic_read_acquire include/linux/atomic/atomic-arch-fallback.h:479 [inline]
RIP: 0010:atomic_read_acquire include/linux/atomic/atomic-instrumented.h:50 [inline]
RIP: 0010:__fget_light fs/file.c:1114 [inline]
RIP: 0010:fdget+0x5a/0x210 fs/file.c:1128
Code: 3c 02 00 0f 85 a7 01 00 00 48 8b 9b b0 08 00 00 be 04 00 00 00 48 89 df e8 f3 5e f0 ff 48 89 da 48 b8 00 00 00 00 00 fc ff df <48> c1 ea 03 0f b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 08 84
RSP: 0018:ffffc90001bcf680 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffff888113b270c0 RCX: ffffffff81be22fd
RDX: ffff888113b270c0 RSI: 0000000000000004 RDI: ffff888113b270c0
RBP: 0000000000000005 R08: 0000000000000000 R09: ffffed1022764e18
R10: ffff888113b270c3 R11: 0000000000000000 R12: 0000000000000020
R13: 0000000000000005 R14: 000000000000000e R15: 0000000000000005
 do_select+0xe22/0x17b0 fs/select.c:531
 core_sys_select+0x459/0xb80 fs/select.c:678
 do_pselect.constprop.0+0x1a0/0x1f0 fs/select.c:760
 __do_sys_pselect6 fs/select.c:803 [inline]
 __se_sys_pselect6 fs/select.c:794 [inline]
 __x64_sys_pselect6+0x183/0x240 fs/select.c:794
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f379b7fc591
Code: 89 44 24 20 4c 8d 64 24 20 48 89 54 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2d 45 31 c9 4d 89 e0 4c 89 f2 b8 0e 01 00 00 0f 05 <48> 89 c3 48 3d 00 f0 ff ff 76 69 48 8b 05 65 58 0d 00 f7 db 64 89
RSP: 002b:00007fff9686bda0 EFLAGS: 00000246 ORIG_RAX: 000000000000010e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f379b7fc591
RDX: 0000000000000000 RSI: 00007fff9686be98 RDI: 000000000000000e
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000564e66b28178 R14: 0000000000000000 R15: 000000000000000d
 </TASK>
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6782
 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264
 call_usermodehelper_exec+0x3c4/0x4d0 kernel/umh.c:442
 call_modprobe kernel/module/kmod.c:103 [inline]
 __request_module+0x3f6/0x6c0 kernel/module/kmod.c:173
 </TASK>
task:syz-executor    state:D
 stack:26784 pid:29981 tgid:29981 ppid:1      flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x105f/0x34b0 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6782
 exp_funnel_lock+0x344/0x3b0 kernel/rcu/tree_exp.h:320
 synchronize_rcu_expedited+0x290/0x450 kernel/rcu/tree_exp.h:976
 namespace_unlock+0x1b5/0x490 fs/namespace.c:1703
 drop_collected_mounts fs/namespace.c:2225 [inline]
 put_mnt_ns fs/namespace.c:5553 [inline]
 put_mnt_ns+0xf4/0x130 fs/namespace.c:5549
 free_nsproxy+0x47/0x470 kernel/nsproxy.c:193
 put_nsproxy include/linux/nsproxy.h:118 [inline]
 switch_task_namespaces+0xeb/0x100 kernel/nsproxy.c:251
 do_exit+0xad8/0x2ce0 kernel/exit.c:938
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088
 get_signal+0x25fb/0x2770 kernel/signal.c:2917
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6194f7dbfb
RSP: 002b:00007ffe775d02f0 EFLAGS: 00000246
 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffed RBX: 0000000000000005 RCX: 00007f6194f7dbfb
RDX: 00007ffe775d0350 RSI: 0000000000008933 RDI: 0000000000000005
RBP: 00007ffe775d0350 R08: 0000000000000008 R09: 00315f6576616c73
R10: 0000000000000021 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f6195c64620 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
task:syz-executor    state:D
 stack:26784 pid:29989 tgid:29989 ppid:1      flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x105f/0x34b0 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6782
 exp_funnel_lock+0x344/0x3b0 kernel/rcu/tree_exp.h:320
 synchronize_rcu_expedited+0x290/0x450 kernel/rcu/tree_exp.h:976
 namespace_unlock+0x1b5/0x490 fs/namespace.c:1703
 drop_collected_mounts fs/namespace.c:2225 [inline]
 put_mnt_ns fs/namespace.c:5553 [inline]
 put_mnt_ns+0xf4/0x130 fs/namespace.c:5549
 free_nsproxy+0x47/0x470 kernel/nsproxy.c:193
 put_nsproxy include/linux/nsproxy.h:118 [inline]
 switch_task_namespaces+0xeb/0x100 kernel/nsproxy.c:251
 do_exit+0xad8/0x2ce0 kernel/exit.c:938
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088
 get_signal+0x25fb/0x2770 kernel/signal.c:2917
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fae221ddbfb
RSP: 002b:00007ffd13265860 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffed RBX: 0000000000000005 RCX: 00007fae221ddbfb
RDX: 00007ffd132658c0 RSI: 0000000000008933 RDI: 0000000000000005
RBP: 00007ffd132658c0 R08: 0000000000000001 R09: 00305f6576616c73
R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000000003
R13: 00007fae22ec4620 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
task:kworker/u8:1    state:I stack:26768 pid:29991 tgid:29991 ppid:2      flags:0x00004000
Workqueue:  0x0
 (events_unbound)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x105f/0x34b0 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6782
 worker_thread+0x2de/0xf00 kernel/workqueue.c:3406
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
task:syz-executor    state:D stack:26784 pid:29995 tgid:29995 ppid:1      flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x105f/0x34b0 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6782
 exp_funnel_lock+0x344/0x3b0 kernel/rcu/tree_exp.h:320
 synchronize_rcu_expedited+0x290/0x450 kernel/rcu/tree_exp.h:976
 namespace_unlock+0x1b5/0x490 fs/namespace.c:1703
 drop_collected_mounts fs/namespace.c:2225 [inline]
 put_mnt_ns fs/namespace.c:5553 [inline]
 put_mnt_ns+0xf4/0x130 fs/namespace.c:5549
 free_nsproxy+0x47/0x470 kernel/nsproxy.c:193
 put_nsproxy include/linux/nsproxy.h:118 [inline]
 switch_task_namespaces+0xeb/0x100 kernel/nsproxy.c:251
 do_exit+0xad8/0x2ce0 kernel/exit.c:938
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088
 get_signal+0x25fb/0x2770 kernel/signal.c:2917
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0b22e2dbfb
RSP: 002b:00007ffe003253b0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffed RBX: 0000000000000005 RCX: 00007f0b22e2dbfb
RDX: 00007ffe00325410 RSI: 0000000000008933 RDI: 0000000000000005
RBP: 00007ffe00325410 R08: 0000000000000001 R09: 00305f6576616c73
R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f0b23b14620 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
task:kworker/u8:4    state:I stack:27328 pid:29996 tgid:29996 ppid:2      flags:0x00004000
Workqueue:  0x0
 (events_unbound)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x105f/0x34b0 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6782
 worker_thread+0x2de/0xf00 kernel/workqueue.c:3406
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
task:syz-executor    state:D stack:26784 pid:30005 tgid:30005 ppid:1      flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x105f/0x34b0 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6782
 exp_funnel_lock+0x344/0x3b0 kernel/rcu/tree_exp.h:320
 synchronize_rcu_expedited+0x290/0x450 kernel/rcu/tree_exp.h:976
 namespace_unlock+0x1b5/0x490 fs/namespace.c:1703
 drop_collected_mounts fs/namespace.c:2225 [inline]
 put_mnt_ns fs/namespace.c:5553 [inline]
 put_mnt_ns+0xf4/0x130 fs/namespace.c:5549
 free_nsproxy+0x47/0x470 kernel/nsproxy.c:193
 put_nsproxy include/linux/nsproxy.h:118 [inline]
 switch_task_namespaces+0xeb/0x100 kernel/nsproxy.c:251
 do_exit+0xad8/0x2ce0 kernel/exit.c:938
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088
 get_signal+0x25fb/0x2770 kernel/signal.c:2917
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2446aafe33
RSP: 002b:00007fffe3abd9f8 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: 000000000000006c RBX: 00007f2447794620 RCX: 00007f2446aafe33
RDX: 000000000000006c RSI: 00007f2447794670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fffe3abda14 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f2447794670 R15: 0000000000000000
 </TASK>
task:kworker/u8:5    state:I
 stack:29680 pid:30006 tgid:30006 ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x105f/0x34b0 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6782
 worker_thread+0x2de/0xf00 kernel/workqueue.c:3406
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
task:kworker/u8:6    state:I stack:30928 pid:30138 tgid:30138 ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5328 [inline]
 __schedule+0x105f/0x34b0 kernel/sched/core.c:6690
 __schedule_loop kernel/sched/core.c:6767 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6782
 worker_thread+0x2de/0xf00 kernel/workqueue.c:3406
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Showing all locks held in the system:
4 locks held by acpid/2535:
 #0: ffff88813c982230 (&dev->event_lock){..-.}-{2:2}, at: input_event drivers/input/input.c:397 [inline]
 #0: ffff88813c982230 (&dev->event_lock){..-.}-{2:2}, at: input_event+0x70/0xa0 drivers/input/input.c:390
 #1: 
ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: input_pass_values+0x8b/0x8e0 drivers/input/input.c:118
 #2: ffffffff89387a58 (kbd_event_lock){..-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #2: ffffffff89387a58 (kbd_event_lock){..-.}-{2:2}, at: kbd_event+0x8a/0x17a0 drivers/tty/vt/keyboard.c:1535
 #3: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #3: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #3: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720
2 locks held by getty/2608:
 #0: ffff888108afe0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
1 lock held by syz.2.5529/29964:
 #0: ffffffff88ec6a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297
1 lock held by syz.3.5530/29968:
 #0: ffffffff88ec6a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329

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