rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-...D } 2674 jiffies s: 98525 root: 0x1/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 1 to CPUs 0: RBP: 00007f632a91c860 R08: 0000000000000000 R09: 4bcbaa321aeee18c R10: 00007ffcb4e283d0 R11: 0000000000000246 R12: 0000000000000000 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 2547 Comm: udevd Not tainted 6.12.0-rc1-syzkaller #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:ffffc90000007048 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: 00007f51e10fac80(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fef68337a8c CR3: 0000000116312000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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 __show_regs+0x25f/0x750 arch/x86/kernel/process_64.c:89 show_trace_log_lvl+0x26c/0x3d0 arch/x86/kernel/dumpstack.c:301 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:341 [inline] input_handle_event+0xf0b/0x14d0 drivers/input/input.c:369 input_event drivers/input/input.c:398 [inline] input_event+0x83/0xa0 drivers/input/input.c:390 input_sync include/linux/input.h:451 [inline] hidinput_report_event+0xb2/0x100 drivers/hid/hid-input.c:1736 hid_report_raw_event+0x274/0x11c0 drivers/hid/hid-core.c:2047 __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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 26 a1 42 fa 48 89 df e8 3e 1e 43 fa f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 f5 60 37 fa 65 8b 05 b6 1d 13 79 85 c0 74 16 5b RSP: 0018:ffffc900018ef920 EFLAGS: 00000246 RAX: 0000000000000006 RBX: ffff88812070c100 RCX: 1ffffffff14ac0e1 RDX: 0000000000000000 RSI: ffffffff8727f1a0 RDI: ffffffff8746ea80 RBP: 0000000000000293 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8a56400f R11: 0000000000000000 R12: ffff888115ce3000 R13: dffffc0000000000 R14: ffff88812070c548 R15: ffff88811aeca140 __netlink_sendskb net/netlink/af_netlink.c:1277 [inline] netlink_sendskb net/netlink/af_netlink.c:1284 [inline] netlink_unicast+0x6c3/0x7f0 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: 0033:0x7f51e1233a4b 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:00007ffd80f69678 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000055d7531f6140 RCX: 00007f51e1233a4b RDX: 0000000000000000 RSI: 00007ffd80f69688 RDI: 0000000000000004 RBP: 000055d7532a05e0 R08: 0000000000000001 R09: fd5cfdc41491bbdf R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000000b1 R14: 0000000000000000 R15: 0000000000000000 R13: 0000000000000001 R14: 00007f632a920658 R15: 0000000000000001 task:modprobe state:R running task stack:25408 pid:3245 tgid:3245 ppid:25651 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x105f/0x34b0 kernel/sched/core.c:6675 do_task_dead+0xd6/0x110 kernel/sched/core.c:6691 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: 0033:0x7f567ffdda90 RSP: 002b:00007ffefd527788 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f56800ce860 RCX: 00007f567ffdda90 RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000001 RBP: 00007f56800ce860 R08: 0000000000000000 R09: b24dfee59f3ddc7a R10: 00007ffefd527640 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f56800d2658 R15: 0000000000000001 Showing all locks held in the system: 4 locks held by udevd/2547: #0: ffff888137156230 (&dev->event_lock ){..-.}-{2:2} , at: input_event drivers/input/input.c:397 [inline] , at: input_event+0x70/0xa0 drivers/input/input.c:390 #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: input_pass_values+0x8b/0x8e0 drivers/input/input.c:118 #2: ffffffff89387ad8 (kbd_event_lock){..-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffffffff89387ad8 (kbd_event_lock){..-.}-{2:2}, at: kbd_event+0x8a/0x17a0 drivers/tty/vt/keyboard.c:1535 #3: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #3: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #3: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720 2 locks held by getty/2605: #0: ffff88810f7fe0a0 (&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/0:7/13315: #0: ffff888105efad48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90001c8fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff888109756190 ( &dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] &dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 1 lock held by syz.2.6703/2825: #0: ffffffff88ec6a78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297 1 lock held by syz.1.6705/2822: #0: ffffffff88ec6a78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329 =============================================