rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-...D } 2645 jiffies s: 2245 root: 0x1/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 1 to CPUs 0: do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11924 Comm: udevd Not tainted 6.12.0-rc3-syzkaller-00051-g07b887f8236e #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: 72 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 f8 ee 0d ff eb a2 e8 81 ef RSP: 0018:ffffc90000006f08 EFLAGS: 00000002 RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: ffffffff82a06c30 RDI: ffffffff93635660 RBP: ffffffff93635620 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000020 R14: fffffbfff26c6b1e R15: dffffc0000000000 FS: 00007f5234f00c80(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fad9179c018 CR3: 000000011193e000 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 printk_stack_address arch/x86/kernel/dumpstack.c:72 [inline] show_trace_log_lvl+0x21f/0x3d0 arch/x86/kernel/dumpstack.c:285 sched_show_task kernel/sched/core.c:7589 [inline] sched_show_task+0x3f0/0x5f0 kernel/sched/core.c:7564 show_state_filter+0xee/0x320 kernel/sched/core.c:7634 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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:skb_end_offset include/linux/skbuff.h:1674 [inline] RIP: 0010:skb_free_head+0xcc/0x1d0 net/core/skbuff.c:1098 Code: 41 5c 41 5d e9 25 c6 82 fb e8 20 c6 82 fb 48 8d bb c4 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 be 00 00 00 8b RSP: 0018:ffffc90001e7f880 EFLAGS: 00000a03 RAX: dffffc0000000000 RBX: ffff8881134e5640 RCX: ffffffff85d318c7 RDX: 0000000000000000 RSI: ffffffff85d31900 RDI: ffff8881134e5704 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88811ceab000 R14: ffff88811ceab140 R15: 0000000000000000 skb_release_data+0x760/0x910 net/core/skbuff.c:1125 skb_release_all net/core/skbuff.c:1190 [inline] __kfree_skb net/core/skbuff.c:1204 [inline] consume_skb net/core/skbuff.c:1436 [inline] consume_skb+0xbf/0x100 net/core/skbuff.c:1430 netlink_unicast_kernel net/netlink/af_netlink.c:1332 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1357 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:2607 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2661 __sys_sendmsg+0x117/0x1f0 net/socket.c:2690 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: 0033:0x7f5235039a4b 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:00007ffe1b18c6b8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000564e256ccd80 RCX: 00007f5235039a4b RDX: 0000000000000000 RSI: 00007ffe1b18c6c8 RDI: 000000000000000c RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000000c3 R14: 0000000000000000 R15: 0000564e256982c0 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fec17118a90 RSP: 002b:00007fffc98c6728 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007fec17209860 RCX: 00007fec17118a90 RDX: 00000000000000e7 RSI: 000000000000003c RDI: 0000000000000001 RBP: 00007fec17209860 R08: 0000000000000001 R09: 00fdbe2a1acb091a R10: 00007fffc98c65e0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fec1720d658 R15: 0000000000000001 Showing all locks held in the system: 5 locks held by kworker/0:1/9: #0: ffff888106ac0148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc9000009fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff888109b06190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff888109b06190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff888109ba9508 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3206 [inline] #3: ffff888109ba9508 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5418 [inline] #3: ffff888109ba9508 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] #3: ffff888109ba9508 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5821 [inline] #3: ffff888109ba9508 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x28aa/0x4f40 drivers/usb/core/hub.c:5903 #4: ffff8881077eed68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5419 [inline] #4: ffff8881077eed68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] #4: ffff8881077eed68 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5821 [inline] #4: ffff8881077eed68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x28d0/0x4f40 drivers/usb/core/hub.c:5903 2 locks held by getty/2608: #0: ffff88810f7960a0 (&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.3.91/11983: #0: ffffffff88ec69f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329 4 locks held by udevd/11924: #0: ffff88811aaca230 (&dev->event_lock){..-.}-{2:2}, at: input_event drivers/input/input.c:397 [inline] #0: ffff88811aaca230 (&dev->event_lock){..-.}-{2:2}, 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: ffffffff893879d8 (kbd_event_lock){..-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #2: ffffffff893879d8 (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 1 lock held by syz.4.92/11937: #0: ffffffff88ec69f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297 =============================================