rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-...D } 2640 jiffies s: 12093 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: 806 Comm: kworker/0:2 Not tainted 6.12.0-rc4-syzkaller-00052-gc6d9e43954bf #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events console_callback RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:413 Code: 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 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 cc cc cc cc e8 31 f0 0d ff eb a0 e8 ba f0 0d RSP: 0018:ffffc90000006f58 EFLAGS: 00000002 RAX: 0000000000000038 RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff82a08975 RDI: ffffffff93637660 RBP: ffffffff93637620 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000038 R14: ffffffff82a08910 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200012b8 CR3: 0000000113a28000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_out drivers/tty/serial/8250/8250.h:142 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3322 [inline] serial8250_console_write+0xf9e/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 show_trace_log_lvl+0x29d/0x3d0 arch/x86/kernel/dumpstack.c:305 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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_is_held_type+0x107/0x150 kernel/locking/lockdep.c:5902 Code: 00 00 b8 ff ff ff ff 65 0f c1 05 0c eb 13 79 83 f8 01 75 2d 9c 58 f6 c4 02 75 43 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 45 31 ed eb RSP: 0018:ffffc90001cdfb70 EFLAGS: 00000292 RAX: 0000000000000046 RBX: ffff88810b306280 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8727f520 RDI: ffffffff8746ebc0 RBP: ffffffff88ebb0e0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88810b3057c0 R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000002 lock_is_held include/linux/lockdep.h:249 [inline] __might_resched+0x473/0x5e0 kernel/sched/core.c:8615 console_lock+0x1b/0xa0 kernel/printk/printk.c:2802 console_callback+0x63/0x4c0 drivers/tty/vt/vt.c:3120 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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:modprobe state:R running task stack:25424 pid:7898 tgid:7898 ppid:788 flags:0x00000002 Call Trace: 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 exit_to_user_mode_loop kernel/entry/common.c:102 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0xdb/0x240 kernel/entry/common.c:231 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fab59b3ca90 RSP: 002b:00007ffff1e9cac8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007fab59c2d860 RCX: 00007fab59b3ca90 RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000001 RBP: 00007fab59c2d860 R08: 0000000000000001 R09: 9d47d2b229ec0669 R10: 00007ffff1e9c980 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fab59c31658 R15: 0000000000000001 task:kworker/u8:0 state:R running task stack:32568 pid:7899 tgid:7899 ppid:7740 flags:0x00004000 Call Trace: __switch_to_asm+0x70/0x70 task:kworker/u8:3 state:R running task stack:32568 pid:7901 tgid:7901 ppid:46 flags:0x00004000 Call Trace: __switch_to_asm+0x70/0x70 task:modprobe state:R running task stack:25424 pid:7902 tgid:7902 ppid:7768 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x105f/0x34b0 kernel/sched/core.c:6690 do_task_dead+0xd6/0x110 kernel/sched/core.c:6706 do_exit+0x1de7/0x2ce0 kernel/exit.c:990 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088 __do_sys_exit_group kernel/exit.c:1099 [inline] __se_sys_exit_group kernel/exit.c:1097 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1097 x64_sys_call+0x14a9/0x16a0 arch/x86/include/generated/asm/syscalls_64.h:232 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: 0033:0x7f386aa45a90 RSP: 002b:00007fff061ab0a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f386ab36860 RCX: 00007f386aa45a90 RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000001 RBP: 00007f386ab36860 R08: 0000000000000001 R09: f3495e0d5d1402a0 R10: 00007fff061aaf60 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f386ab3a658 R15: 0000000000000001 task:kworker/u8:2 state:R running task stack:32568 pid:7904 tgid:7904 ppid:7768 flags:0x00004000 Call Trace: __switch_to_asm+0x70/0x70 task:kworker/u8:1 state:R running task stack:32568 pid:7905 tgid:7905 ppid:7750 flags:0x00004000 Call Trace: __switch_to_asm+0x70/0x70 task:kworker/u8:6 state:R running task stack:32568 pid:7906 tgid:7906 ppid:788 flags:0x00004000 Call Trace: __switch_to_asm+0x70/0x70 Showing all locks held in the system: 4 locks held by kworker/1:1/38: 2 locks held by kworker/u8:3/46: #0: ffff888100089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90000517d80 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 2 locks held by kworker/u8:6/788: #0: ffff888100089148 ((wq_completion)events_unbound){+.+.}-{0:0} , at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90001c0fd80 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 6 locks held by kworker/0:2/806: #0: ffff888100080948 ((wq_completion)events ){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90001cdfd80 (console_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff88811998e230 (&dev->event_lock){..-.}-{2:2}, at: input_event drivers/input/input.c:397 [inline] #2: ffff88811998e230 (&dev->event_lock){..-.}-{2:2}, at: input_event+0x70/0xa0 drivers/input/input.c:390 #3: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] (rcu_read_lock){....}-{1:2}, at: input_pass_values+0x8b/0x8e0 drivers/input/input.c:118 #4: ffffffff89387a58 (kbd_event_lock){..-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] (kbd_event_lock){..-.}-{2:2}, at: kbd_event+0x8a/0x17a0 drivers/tty/vt/keyboard.c:1535 #5: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #5: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #5: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720 2 locks held by getty/2611: #0: ffff888106bc70a0 ( &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 3 locks held by kworker/1:3/4921: 5 locks held by kworker/0:3/4940: 1 lock held by syz.3.759/7711: #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.2.760/7722: #0: ffffffff88ec6a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329 =============================================