rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-...D
 } 2645 jiffies s: 29617 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: 2533 Comm: syslogd 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: dffffc0000000000 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:  00007fd8b144b380(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200012b8 CR3: 0000000116324000 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+0x535/0x710 drivers/hid/hid-core.c:1652
 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:__mutex_lock_common kernel/locking/mutex.c:607 [inline]
RIP: 0010:__mutex_lock+0x13f/0x9c0 kernel/locking/mutex.c:752
Code: 29 48 8d 7b 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 64 06 00 00 48 3b 5b 60 0f 85 92 01 00 00 <bf> 01 00 00 00 e8 a7 5a 38 fa 48 8d 43 68 31 d2 31 c9 48 89 85 f8
RSP: 0018:ffffc900019cf8d0 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffff888114c936e0 RCX: 1ffffffff2695730
RDX: 1ffff110229926e8 RSI: 0000000000000000 RDI: ffff888114c93740
RBP: ffffc900019cf9f0 R08: ffffffff863c9c57 R09: 0000000000000000
R10: ffffc900019cfa10 R11: 0000000000000000 R12: 1ffff92000339f24
R13: 0000000000000002 R14: dffffc0000000000 R15: 0000000000000000
 __unix_dgram_recvmsg+0x267/0xdd0 net/unix/af_unix.c:2432
 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2537
 sock_recvmsg_nosec net/socket.c:1051 [inline]
 sock_recvmsg+0x1f6/0x250 net/socket.c:1073
 sock_read_iter+0x2bb/0x3b0 net/socket.c:1143
 new_sync_read fs/read_write.c:488 [inline]
 vfs_read+0xa3b/0xbd0 fs/read_write.c:569
 ksys_read+0x1fa/0x260 fs/read_write.c:712
 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: 0033:0x7fd8b159fb6a
Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffda8eadd78 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fd8b159fb6a
RDX: 00000000000000ff RSI: 000055d5fb79f300 RDI: 0000000000000000
RBP: 000055d5fb79f2c0 R08: 0000000000000001 R09: 0000000000000000
R10: 00007fd8b173e3a3 R11: 0000000000000246 R12: 000055d5fb79f34c
R13: 000055d5fb79f300 R14: 0000000000000000 R15: 00007fd8b1782a80
 </TASK>
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/0:2/804:
4 locks held by syslogd/2533:
 #0: ffff8881067a8230 (&dev->event_lock){..-.}-{2:2}, at: input_event drivers/input/input.c:397 [inline]
 #0: ffff8881067a8230 (&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]
 #1: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: 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/2609:
 #0: ffff888108edb0a0 (&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
5 locks held by kworker/0:6/5090:
4 locks held by udevd/29295:
 #0: ffff888121b90418 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182
 #1: ffff88812a6f4888 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154
 #2: ffff888119d2d968 (kn->active#18){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155
 #3: ffff8881067ab190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:1019 [inline]
 #3: ffff8881067ab190 (&dev->mutex){....}-{3:3}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
1 lock held by syz.3.1879/31748:
 #0: ffffffff88ec6a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329
1 lock held by syz.0.1880/31755:
 #0: ffffffff88ec6a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297

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