rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-...D
 } 2664 jiffies s: 12509 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: 2548 Comm: udevd Not tainted 6.12.0-rc1-syzkaller-00027-g4a9fe2a8ac53 #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: 6d 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 38 eb 0d ff eb a2 e8 c1 eb
RSP: 0018:ffffc90000006f08 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff82a07780 RDI: ffffffff936356a0
RBP: ffffffff93635660 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff26c6b26 R15: dffffc0000000000
FS:  00007fbd9a487c80(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b318e8ff8 CR3: 00000001164b2000 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:7582 [inline]
 sched_show_task+0x3f0/0x5f0 kernel/sched/core.c:7557
 show_state_filter+0xee/0x320 kernel/sched/core.c:7627
 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+0x17c3/0x38d0 drivers/usb/gadget/udc/dummy_hcd.c:1988
 __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:1037 [inline]
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1037
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:skwq_has_sleeper include/net/sock.h:2272 [inline]
RIP: 0010:sock_def_readable+0x144/0x610 net/core/sock.c:3441
Code: fb f0 83 44 24 fc 00 49 8d 6d 40 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 93 04 00 00 49 8b 45 40 <48> 39 c5 74 17 e8 02 cb 84 fb ba c3 00 00 00 be 01 00 00 00 4c 89
RSP: 0018:ffffc900016bf910 EFLAGS: 00000246
RAX: ffff888112db16e8 RBX: ffff88810630c000 RCX: ffffffff85d11c51
RDX: 1ffff11022ea37f8 RSI: ffffffff85d119eb RDI: 0000000000000005
RBP: ffff88811751bfc0 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff88810630c180
R13: ffff88811751bf80 R14: ffff88810630c548 R15: ffff8881067dc3c0
 __netlink_sendskb net/netlink/af_netlink.c:1278 [inline]
 netlink_sendskb net/netlink/af_netlink.c:1284 [inline]
 netlink_unicast+0x6f1/0x7f0 net/netlink/af_netlink.c:1372
 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:729 [inline]
 __sock_sendmsg net/socket.c:744 [inline]
 ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2602
 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2656
 __sys_sendmsg+0x117/0x1f0 net/socket.c:2685
 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: 0033:0x7fbd9a5c0a4b
Code: ff 89 ef 48 89 04 24 e8 22 56 f9 ff 48 8b 04 24 48 83 c4 20 5d c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6d 48 8b 15 ae c3 0c 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffc466a8008 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000055bf1a788140 RCX: 00007fbd9a5c0a4b
RDX: 0000000000000000 RSI: 00007ffc466a8018 RDI: 0000000000000004
RBP: 000055bf1a7b1b70 R08: 0000000000000001 R09: 564af071240e92c9
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000000af R14: 0000000000000000 R15: 0000000000000000
 </TASK>
 </TASK>

Showing all locks held in the system:
2 locks held by rcu_preempt/16:
 #0: ffff8881f593d6d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x1f/0x30 kernel/sched/core.c:593
 #1: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #1: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: __update_idle_core+0x58/0x5d0 kernel/sched/fair.c:7597
5 locks held by udevd/2548:
 #0: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: sock_def_readable+0xa7/0x610 net/core/sock.c:3439
 #1: ffff88811ef5e230 (&dev->event_lock){..-.}-{2:2}, at: input_event drivers/input/input.c:397 [inline]
 #1: ffff88811ef5e230 (&dev->event_lock){..-.}-{2:2}, at: input_event+0x70/0xa0 drivers/input/input.c:390
 #2: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #2: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #2: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: input_pass_values+0x8b/0x8e0 drivers/input/input.c:118
 #3: ffffffff89387ad8 (kbd_event_lock){..-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #3: ffffffff89387ad8 (kbd_event_lock){..-.}-{2:2}, at: kbd_event+0x8a/0x17a0 drivers/tty/vt/keyboard.c:1535
 #4: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #4: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #4: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720
2 locks held by getty/2606:
 #0: ffff888113afa0a0 (&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.3.803/7663:
 #0: ffffffff88ec6a78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329
1 lock held by syz.1.806/7658:
 #0: ffffffff88ec6a78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297

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