binder: 21215:21220 ioctl 4090ae82 800002c0 returned -22 ===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected syzkaller #0 Tainted: G L ----------------------------------------------------- syz.3.12642/21220 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8e60a058 (tasklist_lock){.+.+}-{3:3}, at: send_sigio+0x101/0x370 fs/fcntl.c:932 and this task is already holding: ffff88807ac59920 (&f_owner->lock){....}-{3:3}, at: send_sigio+0x38/0x370 fs/fcntl.c:918 which would create a new lock dependency: (&f_owner->lock){....}-{3:3} -> (tasklist_lock){.+.+}-{3:3} but this new dependency connects a SOFTIRQ-irq-safe lock: (&dev->event_lock#2){..-.}-{3:3} ... which became SOFTIRQ-irq-safe at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 class_spinlock_irqsave_constructor include/linux/spinlock.h:619 [inline] input_event+0x71/0xc0 drivers/input/input.c:395 input_report_key include/linux/input.h:439 [inline] aiptek_irq+0xbaf/0x28e0 drivers/input/tablet/aiptek.c:670 __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1655 dummy_timer+0xbc0/0x4650 drivers/usb/gadget/udc/dummy_hcd.c:2005 __run_hrtimer kernel/time/hrtimer.c:1930 [inline] __hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994 hrtimer_run_softirq+0x17a/0x240 kernel/time/hrtimer.c:2011 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 write_comp_data kernel/kcov.c:270 [inline] __sanitizer_cov_trace_switch+0x100/0x130 kernel/kcov.c:351 insn_get_immediate+0xf0/0x1280 arch/x86/lib/insn.c:686 insn_get_length arch/x86/lib/insn.c:745 [inline] insn_decode+0x30e/0x4f0 arch/x86/lib/insn.c:784 arch_jump_entry_size arch/x86/kernel/jump_label.c:24 [inline] __jump_label_patch+0x114/0x4a0 arch/x86/kernel/jump_label.c:45 arch_jump_label_transform_queue+0x69/0x110 arch/x86/kernel/jump_label.c:137 __jump_label_update+0x185/0x380 kernel/jump_label.c:513 static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate+0x1fe/0x290 mm/kfence/core.c:913 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{3:3} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232 __do_wait+0xde/0x740 kernel/exit.c:1679 do_wait+0x1e7/0x510 kernel/exit.c:1723 kernel_wait+0xd6/0x1c0 kernel/exit.c:1899 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 other info that might help us debug this: Chain exists of: &dev->event_lock#2 --> &f_owner->lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&dev->event_lock#2); lock(&f_owner->lock); lock(&dev->event_lock#2); *** DEADLOCK *** 5 locks held by syz.3.12642/21220: #0: ffff888026a24410 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff88804a0f6880 (&type->i_mutex_dir_key#5){++++}-{4:4}, at: inode_lock include/linux/fs.h:1029 [inline] #1: ffff88804a0f6880 (&type->i_mutex_dir_key#5){++++}-{4:4}, at: open_last_lookups fs/namei.c:4608 [inline] #1: ffff88804a0f6880 (&type->i_mutex_dir_key#5){++++}-{4:4}, at: path_openat+0xb4c/0x3860 fs/namei.c:4855 #2: ffffffff9a4af9f8 (&fsnotify_mark_srcu){.+.?}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline] #2: ffffffff9a4af9f8 (&fsnotify_mark_srcu){.+.?}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline] #2: ffffffff9a4af9f8 (&fsnotify_mark_srcu){.+.?}-{0:0}, at: fsnotify+0x74c/0x1ae0 fs/notify/fsnotify.c:563 #3: ffff88807eb86358 (&mark->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:342 [inline] #3: ffff88807eb86358 (&mark->lock){+.+.}-{3:3}, at: dnotify_handle_event+0x62/0x440 fs/notify/dnotify/dnotify.c:105 #4: ffff88807ac59920 (&f_owner->lock){....}-{3:3}, at: send_sigio+0x38/0x370 fs/fcntl.c:918 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&dev->event_lock#2){..-.}-{3:3} { IN-SOFTIRQ-W at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 class_spinlock_irqsave_constructor include/linux/spinlock.h:619 [inline] input_event+0x71/0xc0 drivers/input/input.c:395 input_report_key include/linux/input.h:439 [inline] aiptek_irq+0xbaf/0x28e0 drivers/input/tablet/aiptek.c:670 __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1655 dummy_timer+0xbc0/0x4650 drivers/usb/gadget/udc/dummy_hcd.c:2005 __run_hrtimer kernel/time/hrtimer.c:1930 [inline] __hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994 hrtimer_run_softirq+0x17a/0x240 kernel/time/hrtimer.c:2011 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 write_comp_data kernel/kcov.c:270 [inline] __sanitizer_cov_trace_switch+0x100/0x130 kernel/kcov.c:351 insn_get_immediate+0xf0/0x1280 arch/x86/lib/insn.c:686 insn_get_length arch/x86/lib/insn.c:745 [inline] insn_decode+0x30e/0x4f0 arch/x86/lib/insn.c:784 arch_jump_entry_size arch/x86/kernel/jump_label.c:24 [inline] __jump_label_patch+0x114/0x4a0 arch/x86/kernel/jump_label.c:45 arch_jump_label_transform_queue+0x69/0x110 arch/x86/kernel/jump_label.c:137 __jump_label_update+0x185/0x380 kernel/jump_label.c:513 static_key_disable_cpuslocked+0xc5/0x1a0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate+0x1fe/0x290 mm/kfence/core.c:913 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166 class_spinlock_irqsave_constructor include/linux/spinlock.h:619 [inline] input_inject_event+0xa4/0x330 drivers/input/input.c:419 kbd_led_trigger_activate+0xbc/0x100 drivers/tty/vt/keyboard.c:1074 led_trigger_set+0x535/0x960 drivers/leds/led-triggers.c:220 led_match_default_trigger drivers/leds/led-triggers.c:277 [inline] led_trigger_set_default+0x260/0x2a0 drivers/leds/led-triggers.c:300 led_classdev_register_ext+0x787/0x9c0 drivers/leds/led-class.c:581 led_classdev_register include/linux/leds.h:274 [inline] input_leds_connect+0x517/0x790 drivers/input/input-leds.c:145 input_attach_handler drivers/input/input.c:1011 [inline] input_register_device+0xce0/0x1140 drivers/input/input.c:2395 atkbd_connect+0x71e/0xa10 drivers/input/keyboard/atkbd.c:1323 serio_connect_driver drivers/input/serio/serio.c:44 [inline] serio_driver_probe+0x82/0xb0 drivers/input/serio/serio.c:748 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x267/0xaf0 drivers/base/dd.c:709 __driver_probe_device+0x1ef/0x380 drivers/base/dd.c:871 driver_probe_device+0x4f/0x240 drivers/base/dd.c:901 __driver_attach+0x34c/0x640 drivers/base/dd.c:1295 bus_for_each_dev+0x23b/0x2c0 drivers/base/bus.c:383 serio_attach_driver drivers/input/serio/serio.c:777 [inline] serio_handle_event+0x1af/0xf80 drivers/input/serio/serio.c:214 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 } ... key at: [] input_allocate_device.__key.7+0x0/0x20 -> (&new->fa_lock){...-}-{3:3} { IN-SOFTIRQ-R at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline] _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240 kill_fasync_rcu fs/fcntl.c:1135 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1159 sock_wake_async+0x137/0x160 net/socket.c:-1 sk_wake_async_rcu include/net/sock.h:2593 [inline] sock_def_readable+0x3c1/0x550 net/core/sock.c:3620 tcp_child_process+0x4d7/0x960 net/ipv4/tcp_minisocks.c:1005 tcp_v6_rcv+0x1d6c/0x2fa0 net/ipv6/tcp_ipv6.c:1827 ip6_protocol_deliver_rcu+0xd95/0x1740 net/ipv6/ip6_input.c:479 ip6_input_finish+0x191/0x370 net/ipv6/ip6_input.c:534 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318 ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:545 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6202 [inline] __netif_receive_skb net/core/dev.c:6315 [inline] process_backlog+0x7dd/0x1950 net/core/dev.c:6666 __napi_poll+0xae/0x340 net/core/dev.c:7733 napi_poll net/core/dev.c:7796 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7953 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:912 [inline] __dev_queue_xmit+0x1fe5/0x3950 net/core/dev.c:4905 NF_HOOK_COND include/linux/netfilter.h:307 [inline] ip6_output+0x340/0x550 net/ipv6/ip6_output.c:246 dst_output include/net/dst.h:470 [inline] NF_HOOK include/linux/netfilter.h:318 [inline] ip6_xmit+0x11e2/0x1af0 net/ipv6/ip6_output.c:379 inet6_csk_xmit+0x3bd/0x6c0 net/ipv6/inet6_connection_sock.c:115 __tcp_transmit_skb+0x26dd/0x4790 net/ipv4/tcp_output.c:1715 tcp_transmit_skb net/ipv4/tcp_output.c:1733 [inline] tcp_write_xmit+0x1be0/0x6540 net/ipv4/tcp_output.c:3061 __tcp_push_pending_frames+0x97/0x380 net/ipv4/tcp_output.c:3244 __tcp_close+0x617/0xfe0 net/ipv4/tcp.c:3222 tcp_close+0x28/0x110 net/ipv4/tcp.c:3313 inet_release+0x143/0x190 net/ipv4/af_inet.c:442 __sock_release net/socket.c:722 [inline] sock_close+0xc3/0x240 net/socket.c:1514 __fput+0x44f/0xa60 fs/file_table.c:510 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0x193/0x680 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] __do_fast_syscall_32+0x45b/0x6f0 arch/x86/entry/syscall_32.c:310 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e INITIAL USE at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_write_lock_irq include/linux/rwlock_api_smp.h:213 [inline] _raw_write_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:330 fasync_remove_entry+0xf1/0x1c0 fs/fcntl.c:1012 setfl fs/fcntl.c:76 [inline] do_fcntl+0x1201/0x1a20 fs/fcntl.c:477 do_compat_fcntl64+0x51e/0x7e0 fs/fcntl.c:800 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x23e/0x6f0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e INITIAL READ USE at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline] _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240 kill_fasync_rcu fs/fcntl.c:1135 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1159 pipe_release+0x19c/0x330 fs/pipe.c:739 __fput+0x44f/0xa60 fs/file_table.c:510 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0x193/0x680 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] __do_fast_syscall_32+0x45b/0x6f0 arch/x86/entry/syscall_32.c:310 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] fasync_insert_entry.__key+0x0/0x20 ... acquired at: __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline] _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240 kill_fasync_rcu fs/fcntl.c:1135 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1159 mousedev_notify_readers+0x6f1/0xc00 drivers/input/mousedev.c:309 mousedev_event+0x602/0x1320 drivers/input/mousedev.c:394 input_handle_events_default+0xd4/0x1a0 drivers/input/input.c:2558 input_pass_values+0x288/0x890 drivers/input/input.c:128 input_event_dispose+0x330/0x6b0 drivers/input/input.c:342 input_inject_event+0x1dc/0x330 drivers/input/input.c:424 evdev_write+0x325/0x4c0 drivers/input/evdev.c:528 vfs_write+0x29a/0xb90 fs/read_write.c:686 ksys_write+0x150/0x270 fs/read_write.c:740 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x23e/0x6f0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> (&f_owner->lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_write_lock_irq include/linux/rwlock_api_smp.h:213 [inline] _raw_write_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:330 __f_setown+0x67/0x370 fs/fcntl.c:136 generic_add_lease fs/locks.c:1924 [inline] generic_setlease+0xacf/0xfd0 fs/locks.c:2000 do_fcntl_add_lease+0x35e/0x470 fs/locks.c:2102 fcntl_setdeleg+0x14c/0x1e0 fs/locks.c:2148 do_fcntl+0xe6d/0x1a20 fs/fcntl.c:564 do_compat_fcntl64+0x51e/0x7e0 fs/fcntl.c:800 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x23e/0x6f0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e INITIAL READ USE at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline] _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240 send_sigio+0x38/0x370 fs/fcntl.c:918 kill_fasync_rcu fs/fcntl.c:1144 [inline] kill_fasync+0x24d/0x4d0 fs/fcntl.c:1159 lease_break_callback+0x26/0x30 fs/locks.c:577 __break_lease+0x81f/0x1ea0 fs/locks.c:1669 break_deleg include/linux/filelock.h:505 [inline] try_break_deleg include/linux/filelock.h:524 [inline] vfs_remove_acl+0x21c/0x830 fs/posix_acl.c:1237 removexattr fs/xattr.c:1027 [inline] file_removexattr fs/xattr.c:1037 [inline] path_removexattrat+0x4c4/0x750 fs/xattr.c:1086 __do_sys_fremovexattr fs/xattr.c:1112 [inline] __se_sys_fremovexattr fs/xattr.c:1110 [inline] __ia32_sys_fremovexattr+0x61/0x70 fs/xattr.c:1110 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x23e/0x6f0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] file_f_owner_allocate.__key+0x0/0x20 ... acquired at: __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline] _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240 send_sigio+0x38/0x370 fs/fcntl.c:918 kill_fasync_rcu fs/fcntl.c:1144 [inline] kill_fasync+0x24d/0x4d0 fs/fcntl.c:1159 lease_break_callback+0x26/0x30 fs/locks.c:577 __break_lease+0x81f/0x1ea0 fs/locks.c:1669 break_deleg include/linux/filelock.h:505 [inline] try_break_deleg include/linux/filelock.h:524 [inline] vfs_remove_acl+0x21c/0x830 fs/posix_acl.c:1237 removexattr fs/xattr.c:1027 [inline] file_removexattr fs/xattr.c:1037 [inline] path_removexattrat+0x4c4/0x750 fs/xattr.c:1086 __do_sys_fremovexattr fs/xattr.c:1112 [inline] __se_sys_fremovexattr fs/xattr.c:1110 [inline] __ia32_sys_fremovexattr+0x61/0x70 fs/xattr.c:1110 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x23e/0x6f0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock: -> (tasklist_lock){.+.+}-{3:3} { HARDIRQ-ON-R at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232 __do_wait+0xde/0x740 kernel/exit.c:1679 do_wait+0x1e7/0x510 kernel/exit.c:1723 kernel_wait+0xd6/0x1c0 kernel/exit.c:1899 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 SOFTIRQ-ON-R at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232 __do_wait+0xde/0x740 kernel/exit.c:1679 do_wait+0x1e7/0x510 kernel/exit.c:1723 kernel_wait+0xd6/0x1c0 kernel/exit.c:1899 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_write_lock_irq include/linux/rwlock_api_smp.h:213 [inline] _raw_write_lock_irq+0x3d/0x50 kernel/locking/spinlock.c:330 copy_process+0x2b4c/0x4440 kernel/fork.c:2411 kernel_clone+0x2d7/0x940 kernel/fork.c:2722 user_mode_thread+0x110/0x180 kernel/fork.c:2798 rest_init+0x23/0x300 init/main.c:727 start_kernel+0x38a/0x3e0 init/main.c:1220 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x147 INITIAL READ USE at: lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232 __do_wait+0xde/0x740 kernel/exit.c:1679 do_wait+0x1e7/0x510 kernel/exit.c:1723 kernel_wait+0xd6/0x1c0 kernel/exit.c:1899 call_usermodehelper_exec_sync kernel/umh.c:136 [inline] call_usermodehelper_exec_work+0xbe/0x230 kernel/umh.c:163 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3397 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3478 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232 send_sigio+0x101/0x370 fs/fcntl.c:932 dnotify_handle_event+0x169/0x440 fs/notify/dnotify/dnotify.c:113 fsnotify_handle_event fs/notify/fsnotify.c:327 [inline] send_to_group fs/notify/fsnotify.c:375 [inline] fsnotify+0x1831/0x1ae0 fs/notify/fsnotify.c:592 fsnotify_name include/linux/fsnotify.h:55 [inline] fsnotify_dirent include/linux/fsnotify.h:61 [inline] fsnotify_create include/linux/fsnotify.h:323 [inline] open_last_lookups fs/namei.c:4614 [inline] path_openat+0x15c2/0x3860 fs/namei.c:4855 do_file_open+0x23e/0x4a0 fs/namei.c:4887 do_sys_openat2+0x113/0x200 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_compat_sys_openat fs/open.c:1432 [inline] __se_compat_sys_openat fs/open.c:1430 [inline] __ia32_compat_sys_openat+0x131/0x160 fs/open.c:1430 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x23e/0x6f0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e stack backtrace: CPU: 0 UID: 0 PID: 21220 Comm: syz.3.12642 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_bad_irq_dependency kernel/locking/lockdep.c:2616 [inline] check_irq_usage kernel/locking/lockdep.c:2857 [inline] check_prev_add kernel/locking/lockdep.c:3169 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x2a94/0x2cf0 kernel/locking/lockdep.c:5237 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_read_lock include/linux/rwlock_api_smp.h:163 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:232 send_sigio+0x101/0x370 fs/fcntl.c:932 dnotify_handle_event+0x169/0x440 fs/notify/dnotify/dnotify.c:113 fsnotify_handle_event fs/notify/fsnotify.c:327 [inline] send_to_group fs/notify/fsnotify.c:375 [inline] fsnotify+0x1831/0x1ae0 fs/notify/fsnotify.c:592 fsnotify_name include/linux/fsnotify.h:55 [inline] fsnotify_dirent include/linux/fsnotify.h:61 [inline] fsnotify_create include/linux/fsnotify.h:323 [inline] open_last_lookups fs/namei.c:4614 [inline] path_openat+0x15c2/0x3860 fs/namei.c:4855 do_file_open+0x23e/0x4a0 fs/namei.c:4887 do_sys_openat2+0x113/0x200 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_compat_sys_openat fs/open.c:1432 [inline] __se_compat_sys_openat fs/open.c:1430 [inline] __ia32_compat_sys_openat+0x131/0x160 fs/open.c:1430 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x23e/0x6f0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf705f01c Code: 90 85 d2 74 0a 89 ce 81 e6 ff 0f 00 00 89 32 85 c0 74 05 c1 e9 0c 89 08 31 c0 5e 5d c3 90 0f 1f 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 58 b8 RSP: 002b:00000000f542c50c EFLAGS: 00000206 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 0000000080000480 RDX: 000000000000275a RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: 90 nop 1: 85 d2 test %edx,%edx 3: 74 0a je 0xf 5: 89 ce mov %ecx,%esi 7: 81 e6 ff 0f 00 00 and $0xfff,%esi d: 89 32 mov %esi,(%rdx) f: 85 c0 test %eax,%eax 11: 74 05 je 0x18 13: c1 e9 0c shr $0xc,%ecx 16: 89 08 mov %ecx,(%rax) 18: 31 c0 xor %eax,%eax 1a: 5e pop %rsi 1b: 5d pop %rbp 1c: c3 ret 1d: 90 nop 1e: 0f 1f 00 nopl (%rax) 21: 51 push %rcx 22: 52 push %rdx 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 ret 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 58 pop %rax 3f: b8 .byte 0xb8