rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-...D } 2637 jiffies s: 44061 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: 2529 Comm: syslogd Not tainted 6.12.0-rc4-syzkaller-00052-gc6d9e43954bf #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:format_decode+0x42e/0xba0 lib/vsprintf.c:2612 Code: fd 7a 0f 84 a7 01 00 00 e8 df 52 6f fa 44 89 ee bf 74 00 00 00 e8 b2 54 6f fa 41 80 fd 74 0f 84 8b 01 00 00 48 89 eb 45 31 ed bd 52 6f fa 48 89 da 41 c6 44 24 05 0a 48 b8 00 00 00 00 00 fc RSP: 0018:ffffc90000006af8 EFLAGS: 00000016 RAX: 0000000000000002 RBX: ffffffff8728c784 RCX: ffffffff86e6a4c5 RDX: ffff888115660000 RSI: 0000000000000075 RDI: 0000000000000000 RBP: ffffffff8728c783 R08: 0000000000000000 R09: 0000000000000075 R10: 000000000000006c R11: 000000000061fd58 R12: ffffc90000006bf8 R13: 000000000000006c R14: 0000000000000075 R15: 0000000000000005 FS: 00007f4193a10380(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcac468828 CR3: 000000011548c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vsnprintf+0x13d/0x1880 lib/vsprintf.c:2755 sprintf+0xcd/0x110 lib/vsprintf.c:3007 print_time kernel/printk/printk.c:1362 [inline] info_print_prefix+0x25c/0x350 kernel/printk/printk.c:1388 record_print_text+0x141/0x400 kernel/printk/printk.c:1437 printk_get_next_message+0x2a6/0x670 kernel/printk/printk.c:2978 console_emit_next_record kernel/printk/printk.c:3046 [inline] console_flush_all+0x6ec/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+0x1b7/0x3d0 arch/x86/kernel/dumpstack.c:285 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:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:87 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:123 [inline] RIP: 0010:lock_is_held_type+0x54/0x150 kernel/locking/lockdep.c:5893 Code: eb 13 79 85 c0 0f 85 ce 00 00 00 65 4c 8b 25 33 26 15 79 41 8b 94 24 94 0a 00 00 85 d2 0f 85 b6 00 00 00 48 89 fd 41 89 f6 9c <8f> 04 24 fa 48 c7 c7 e0 f4 27 87 45 31 ff e8 89 16 00 00 4d 8d ac RSP: 0018:ffffc900017cfc58 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff920002f9f96 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff88ebb0e0 RBP: ffffffff88ebb0e0 R08: 0000000000000003 R09: 0000000000008000 R10: 0000000000008000 R11: 0000000000000000 R12: ffff888115660000 R13: 00000000ffffffff R14: 00000000ffffffff R15: 1ffff920002f9faf lock_is_held include/linux/lockdep.h:249 [inline] __might_resched+0x473/0x5e0 kernel/sched/core.c:8615 percpu_down_read include/linux/percpu-rwsem.h:49 [inline] __sb_start_write include/linux/fs.h:1716 [inline] sb_start_write include/linux/fs.h:1852 [inline] file_start_write include/linux/fs.h:2931 [inline] vfs_write+0x98c/0x1140 fs/read_write.c:679 ksys_write+0x12f/0x260 fs/read_write.c:736 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: 0033:0x7f4193b64bf2 Code: 89 c7 48 89 44 24 08 e8 7b 34 fa ff 48 8b 44 24 08 48 83 c4 28 c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 07 a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffd959c0068 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f4193b64bf2 RDX: 000000000000005b RSI: 0000562df03ee600 RDI: 0000000000000003 RBP: 0000562df03ee600 R08: 0000000000000001 R09: 0000000000000000 R10: 00007f4193d033a3 R11: 0000000000000246 R12: 000000000000005b R13: 00007f4193a10300 R14: 0000000000000006 R15: 0000562df03ee410 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6782 do_wait+0x1dd/0x570 kernel/exit.c:1697 kernel_wait4+0x16c/0x280 kernel/exit.c:1851 __do_sys_wait4+0xd2/0x170 kernel/exit.c:1881 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 task:syz-executor state:D stack:26096 pid:18966 tgid:18966 ppid:1 flags:0x00004006 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 exp_funnel_lock+0x344/0x3b0 kernel/rcu/tree_exp.h:320 synchronize_rcu_expedited+0x290/0x450 kernel/rcu/tree_exp.h:976 namespace_unlock+0x1b5/0x490 fs/namespace.c:1703 drop_collected_mounts fs/namespace.c:2225 [inline] put_mnt_ns fs/namespace.c:5553 [inline] put_mnt_ns+0xf4/0x130 fs/namespace.c:5549 free_nsproxy+0x47/0x470 kernel/nsproxy.c:193 put_nsproxy include/linux/nsproxy.h:118 [inline] switch_task_namespaces+0xeb/0x100 kernel/nsproxy.c:251 do_exit+0xad8/0x2ce0 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe9e90cdbfb RSP: 002b:00007fffb13284b0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffed RBX: 0000000000000005 RCX: 00007fe9e90cdbfb RDX: 00007fffb1328510 RSI: 0000000000008933 RDI: 0000000000000005 RBP: 00007fffb1328510 R08: 0000000000000008 R09: 00315f6576616c73 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 00007fe9e9db4620 R14: 0000000000000000 R15: 0000000000000000 task:syz-executor state:D stack:26784 pid:18969 tgid:18969 ppid:1 flags:0x00004006 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 exp_funnel_lock+0x344/0x3b0 kernel/rcu/tree_exp.h:320 synchronize_rcu_expedited+0x290/0x450 kernel/rcu/tree_exp.h:976 namespace_unlock+0x1b5/0x490 fs/namespace.c:1703 drop_collected_mounts fs/namespace.c:2225 [inline] put_mnt_ns fs/namespace.c:5553 [inline] put_mnt_ns+0xf4/0x130 fs/namespace.c:5549 free_nsproxy+0x47/0x470 kernel/nsproxy.c:193 put_nsproxy include/linux/nsproxy.h:118 [inline] switch_task_namespaces+0xeb/0x100 kernel/nsproxy.c:251 do_exit+0xad8/0x2ce0 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff1e9aadbfb RSP: 002b:00007ffda46cbd30 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffed RBX: 0000000000000005 RCX: 00007ff1e9aadbfb RDX: 00007ffda46cbd90 RSI: 0000000000008933 RDI: 0000000000000005 RBP: 00007ffda46cbd90 R08: 0000000000000008 R09: 00305f6576616c73 R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000003 R13: 00007ff1ea794620 R14: 0000000000000000 R15: 0000000000000000 task:syz-executor state:D stack:26720 pid:18971 tgid:18971 ppid:1 flags:0x00004006 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 exp_funnel_lock+0x344/0x3b0 kernel/rcu/tree_exp.h:320 synchronize_rcu_expedited+0x290/0x450 kernel/rcu/tree_exp.h:976 namespace_unlock+0x1b5/0x490 fs/namespace.c:1703 drop_collected_mounts fs/namespace.c:2225 [inline] put_mnt_ns fs/namespace.c:5553 [inline] put_mnt_ns+0xf4/0x130 fs/namespace.c:5549 free_nsproxy+0x47/0x470 kernel/nsproxy.c:193 put_nsproxy include/linux/nsproxy.h:118 [inline] switch_task_namespaces+0xeb/0x100 kernel/nsproxy.c:251 do_exit+0xad8/0x2ce0 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4ceb1edbfb RSP: 002b:00007ffdb3909470 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffed RBX: 0000000000000005 RCX: 00007f4ceb1edbfb RDX: 00007ffdb39094d0 RSI: 0000000000008933 RDI: 0000000000000005 RBP: 00007ffdb39094d0 R08: 0000000000000003 R09: 00315f6576616c73 R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f4cebed4620 R14: 0000000000000000 R15: 0000000000000000 task:syz-executor state:D stack:26784 pid:18988 tgid:18988 ppid:1 flags:0x00004006 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 exp_funnel_lock+0x344/0x3b0 kernel/rcu/tree_exp.h:320 synchronize_rcu_expedited+0x290/0x450 kernel/rcu/tree_exp.h:976 namespace_unlock+0x1b5/0x490 fs/namespace.c:1703 drop_collected_mounts fs/namespace.c:2225 [inline] put_mnt_ns fs/namespace.c:5553 [inline] put_mnt_ns+0xf4/0x130 fs/namespace.c:5549 free_nsproxy+0x47/0x470 kernel/nsproxy.c:193 put_nsproxy include/linux/nsproxy.h:118 [inline] switch_task_namespaces+0xeb/0x100 kernel/nsproxy.c:251 do_exit+0xad8/0x2ce0 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f048091dbfb RSP: 002b:00007ffd5b66b3c0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffed RBX: 0000000000000005 RCX: 00007f048091dbfb RDX: 00007ffd5b66b420 RSI: 0000000000008933 RDI: 0000000000000005 RBP: 00007ffd5b66b420 R08: 0000000000000001 R09: 00305f6576616c73 R10: 0000000000000021 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f0481604620 R14: 0000000000000000 R15: 0000000000000000 task:syz-executor state:D stack:25616 pid:18991 tgid:18991 ppid:1 flags:0x00004006 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 exp_funnel_lock+0x344/0x3b0 kernel/rcu/tree_exp.h:320 synchronize_rcu_expedited+0x290/0x450 kernel/rcu/tree_exp.h:976 namespace_unlock+0x1b5/0x490 fs/namespace.c:1703 drop_collected_mounts fs/namespace.c:2225 [inline] put_mnt_ns fs/namespace.c:5553 [inline] put_mnt_ns+0xf4/0x130 fs/namespace.c:5549 free_nsproxy+0x47/0x470 kernel/nsproxy.c:193 put_nsproxy include/linux/nsproxy.h:118 [inline] switch_task_namespaces+0xeb/0x100 kernel/nsproxy.c:251 do_exit+0xad8/0x2ce0 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1088 get_signal+0x25fb/0x2770 kernel/signal.c:2917 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x147/0x260 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2e9457fe33 RSP: 002b:00007ffc270e7d08 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: 0000000000000068 RBX: 00007f2e95264620 RCX: 00007f2e9457fe33 RDX: 0000000000000068 RSI: 00007f2e95264670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc270e7d24 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f2e95264670 R15: 0000000000000000 task:kworker/u8:7 state:I stack:26704 pid:19066 tgid:19066 ppid:2 flags:0x00004000 Workqueue: 0x0 (events_unbound) 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 worker_thread+0x2de/0xf00 kernel/workqueue.c:3406 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 Showing all locks held in the system: 5 locks held by kworker/0:0/8: 4 locks held by syslogd/2529: #0: ffff88811539a230 (&dev->event_lock){..-.}-{2:2}, at: input_event drivers/input/input.c:397 [inline] #0: ffff88811539a230 (&dev->event_lock){..-.}-{2:2}, at: input_event+0x70/0xa0 drivers/input/input.c:390 #1: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #1: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: input_pass_values+0x8b/0x8e0 drivers/input/input.c:118 #2: ffffffff89387a58 (kbd_event_lock){..-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #2: ffffffff89387a58 (kbd_event_lock){..-.}-{2:2}, at: kbd_event+0x8a/0x17a0 drivers/tty/vt/keyboard.c:1535 #3: ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] ffffffff88ebb140 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720 2 locks held by getty/2605: #0: ffff88810f7340a0 (&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.0.3108/18926: #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.2.3113/18941: #0: ffffffff88ec6a38 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329 =============================================