rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: {
 1-.... } 2634 jiffies s: 8017 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):

Sending NMI from CPU 0 to CPUs 1:
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
NMI backtrace for cpu 1
CPU: 1 PID: 921 Comm: kworker/1:2 Not tainted 6.8.0-rc1-syzkaller-00169-gecb1b8288dc7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:io_serial_out+0x7a/0xb0 drivers/tty/serial/8250/8250_port.c:417
Code: fc 89 e9 41 d3 e7 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 00 8d 14 fd 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 89 e9 80 e1 07 38 c1 7c ab 48 89 ef e8
RSP: 0018:ffffc900001eff70 EFLAGS: 00000002
RAX: 0000000000000020 RBX: ffffffff9245bf00 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020
RBP: 0000000000000000 R08: ffffffff84d97877 R09: 1ffff11003b18046
R10: dffffc0000000000 R11: ffffed1003b18047 R12: dffffc0000000000
R13: 0000000000000020 R14: 0000000000000020 R15: 00000000000003f8
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555567a5938 CR3: 000000000d331000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 serial8250_console_write+0x1281/0x1810 drivers/tty/serial/8250/8250_port.c:3444
 console_emit_next_record kernel/printk/printk.c:2901 [inline]
 console_flush_all+0x7fe/0xec0 kernel/printk/printk.c:2967
 console_unlock+0x137/0x4c0 kernel/printk/printk.c:3036
 vprintk_emit+0x504/0x720 kernel/printk/printk.c:2303
 dev_vprintk_emit+0x2aa/0x330 drivers/base/core.c:4850
 dev_printk_emit+0xd9/0x120 drivers/base/core.c:4861
 _dev_warn+0x11e/0x170 drivers/base/core.c:4917
 usb_rx_callback_intf0+0x152/0x190 drivers/media/rc/imon.c:1771
 __usb_hcd_giveback_urb+0x371/0x530 drivers/usb/core/hcd.c:1650
 dummy_timer+0x8ad/0x3200 drivers/usb/gadget/udc/dummy_hcd.c:1987
 call_timer_fn+0x176/0x5e0 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x61d/0x830 kernel/time/timer.c:2038
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2051
 __do_softirq+0x2bb/0x92e kernel/softirq.c:553
 do_softirq+0x117/0x1e0 kernel/softirq.c:454
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x1b1/0x1f0 kernel/softirq.c:381
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline]
 nsim_dev_trap_report_work+0x759/0xa90 drivers/net/netdevsim/dev.c:850
 process_one_work kernel/workqueue.c:2633 [inline]
 process_scheduled_works+0x90b/0x1400 kernel/workqueue.c:2706
 worker_thread+0xa5b/0xff0 kernel/workqueue.c:2787
 kthread+0x2cf/0x360 kernel/kthread.c:388
 ret_from_fork+0x44/0x70 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </TASK>
imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored
imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored