rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2639 jiffies s: 1129 root: 0x1/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 1 to CPUs 0: imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored NMI backtrace for cpu 0 CPU: 0 PID: 5042 Comm: kworker/0:4 Not tainted 6.4.0-rc3-syzkaller-00032-g933174ae28ba #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/16/2023 Workqueue: usb_hub_wq hub_event RIP: 0010:io_serial_in+0x87/0xa0 drivers/tty/serial/8250/8250_port.c:470 Code: 3a fc fc 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 16 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c c3 e8 8c 03 4f fd eb a6 e8 e5 03 4f fd eb e3 RSP: 0018:ffffc90000007478 EFLAGS: 00000002 RAX: dffffc0000000060 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: ffffffff848808c0 RDI: ffffffff920c51c0 RBP: ffffffff920c5180 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000020 R14: fffffbfff2418a89 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb5960d5368 CR3: 000000000c571000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_in drivers/tty/serial/8250/8250.h:118 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:140 [inline] wait_for_lsr+0xd7/0x180 drivers/tty/serial/8250/8250_port.c:2110 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3381 [inline] serial8250_console_write+0xccf/0x1010 drivers/tty/serial/8250/8250_port.c:3459 console_emit_next_record kernel/printk/printk.c:2877 [inline] console_flush_all+0x49c/0xcc0 kernel/printk/printk.c:2933 console_unlock+0xb8/0x1f0 kernel/printk/printk.c:3007 vprintk_emit+0x1bd/0x600 kernel/printk/printk.c:2307 dev_vprintk_emit drivers/base/core.c:4840 [inline] dev_printk_emit+0xda/0x120 drivers/base/core.c:4851 __dev_printk+0xf8/0x270 drivers/base/core.c:4863 _dev_warn+0xdc/0x120 drivers/base/core.c:4907 usb_rx_callback_intf0+0x11b/0x1a0 drivers/media/rc/imon.c:1771 __usb_hcd_giveback_urb+0x2b6/0x5c0 drivers/usb/core/hcd.c:1671 usb_hcd_giveback_urb+0x384/0x430 drivers/usb/core/hcd.c:1754 dummy_timer+0x13b6/0x3400 drivers/usb/gadget/udc/dummy_hcd.c:1988 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700 expire_timers+0x29b/0x4b0 kernel/time/timer.c:1751 __run_timers kernel/time/timer.c:2022 [inline] __run_timers kernel/time/timer.c:1995 [inline] run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035 __do_softirq+0x1d4/0x905 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x114/0x190 kernel/softirq.c:650 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:200 Code: 06 d9 8e 02 66 0f 1f 44 00 00 f3 0f 1e fa 48 8b be a8 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 0f 1e fa 65 8b 05 ed 78 7f 7e 89 c1 48 8b 34 24 81 e1 00 01 00 RSP: 0018:ffffc90003afec80 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000000000 RDX: ffff88802003bb80 RSI: ffffffff81685b25 RDI: 0000000000000007 RBP: ffffffff8d264d18 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8d264cc0 R14: dffffc0000000000 R15: 0000000000000001 console_emit_next_record arch/x86/include/asm/irqflags.h:42 [inline] console_flush_all+0x61b/0xcc0 kernel/printk/printk.c:2933 console_unlock+0xb8/0x1f0 kernel/printk/printk.c:3007 vprintk_emit+0x1bd/0x600 kernel/printk/printk.c:2307 dev_vprintk_emit drivers/base/core.c:4840 [inline] dev_printk_emit+0xda/0x120 drivers/base/core.c:4851 __dev_printk+0xf8/0x270 drivers/base/core.c:4863 _dev_info+0xdc/0x120 drivers/base/core.c:4909 imon_probe+0x7f2/0x3630 drivers/media/rc/imon.c:2474 usb_probe_interface+0x30f/0x960 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x240/0xca0 drivers/base/dd.c:658 __driver_probe_device+0x1df/0x4b0 drivers/base/dd.c:800 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:830 __device_attach_driver+0x1d4/0x2e0 drivers/base/dd.c:958 bus_for_each_drv+0x149/0x1d0 drivers/base/bus.c:457 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1030 bus_probe_device+0x17c/0x1c0 drivers/base/bus.c:532 device_add+0x112d/0x1a40 drivers/base/core.c:3625 usb_set_configuration+0x1196/0x1bc0 drivers/usb/core/message.c:2211 usb_generic_driver_probe+0xcf/0x130 drivers/usb/core/generic.c:238 usb_probe_device+0xd8/0x2c0 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x240/0xca0 drivers/base/dd.c:658 __driver_probe_device+0x1df/0x4b0 drivers/base/dd.c:800 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:830 __device_attach_driver+0x1d4/0x2e0 drivers/base/dd.c:958 bus_for_each_drv+0x149/0x1d0 drivers/base/bus.c:457 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1030 bus_probe_device+0x17c/0x1c0 drivers/base/bus.c:532 device_add+0x112d/0x1a40 drivers/base/core.c:3625 usb_new_device+0xcb2/0x19d0 drivers/usb/core/hub.c:2575 hub_port_connect drivers/usb/core/hub.c:5407 [inline] hub_port_connect_change drivers/usb/core/hub.c:5551 [inline] port_event drivers/usb/core/hub.c:5711 [inline] hub_event+0x2d9e/0x4e40 drivers/usb/core/hub.c:5793 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405 process_scheduled_works kernel/workqueue.c:2468 [inline] worker_thread+0x881/0x10c0 kernel/workqueue.c:2554 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 5.341 msecs imon 6-1:0.0: 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 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 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 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 6-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 6-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 6-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 6-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 6-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 4-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored usb 2-1: USB disconnect, device number 5 imon 2-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 6-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 6-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 6-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 3-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 1-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored imon 5-1:0.0: imon usb_rx_callback_intf0: status(-71): ignored usb 2-1: new high-speed USB device number 6 using dummy_hcd usb 2-1: Using ep0 maxpacket: 16 usb 2-1: config 0 interface 0 altsetting 0 endpoint 0x8B has an invalid bInterval 0, changing to 7 usb 2-1: New USB device found, idVendor=15c2, idProduct=0040, bcdDevice= 7.f3 usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 usb 2-1: Product: syz usb 2-1: Manufacturer: syz usb 2-1: SerialNumber: syz usb 2-1: config 0 descriptor?? input: iMON Panel, Knob and Mouse(15c2:0040) as /devices/platform/dummy_hcd.1/usb2/2-1/2-1:0.0/input/input58 rc_core: IR keymap rc-imon-pad not found Registered IR keymap rc-empty imon 2-1:0.0: Looks like you're trying to use an IR protocol this device does not support imon 2-1:0.0: Unsupported IR protocol specified, overriding to iMON IR protocol rc rc3: iMON Remote (15c2:0040) as /devices/platform/dummy_hcd.1/usb2/2-1/2-1:0.0/rc/rc3 input: iMON Remote (15c2:0040) as /devices/platform/dummy_hcd.1/usb2/2-1/2-1:0.0/rc/rc3/input60