===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 6.15.0-rc7-syzkaller #0 Not tainted ----------------------------------------------------- syz.2.3820/19503 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8dc0c058 (tasklist_lock){.+.+}-{3:3}, at: send_sigurg+0x12b/0x420 fs/fcntl.c:967 and this task is already holding: ffff888143ae5120 (&f_owner->lock){....}-{3:3}, at: send_sigurg+0x55/0x420 fs/fcntl.c:951 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+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0xab/0x320 drivers/input/input.c:418 kd_sound_helper+0x101/0x210 drivers/tty/vt/keyboard.c:256 input_handler_for_each_handle+0xfe/0x1c0 drivers/input/input.c:2554 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers kernel/time/timer.c:2414 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426 run_timer_base kernel/time/timer.c:2435 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 native_irq_enable arch/x86/include/asm/irqflags.h:42 [inline] arch_local_irq_enable arch/x86/include/asm/irqflags.h:119 [inline] raw_spin_rq_unlock_irq kernel/sched/sched.h:1525 [inline] finish_lock_switch kernel/sched/core.c:5130 [inline] finish_task_switch+0x26b/0x950 kernel/sched/core.c:5248 context_switch kernel/sched/core.c:5385 [inline] __schedule+0x16ea/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 __skb_wait_for_more_packets+0x3a2/0x580 net/core/datagram.c:121 __unix_dgram_recvmsg+0x285/0xdc0 net/unix/af_unix.c:2433 sock_recvmsg_nosec net/socket.c:1017 [inline] sock_recvmsg+0x229/0x270 net/socket.c:1039 sock_read_iter+0x231/0x2f0 net/socket.c:1109 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x4cd/0x980 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:713 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{3:3} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1662 do_wait+0x1f8/0x520 kernel/exit.c:1706 kernel_wait+0xab/0x170 kernel/exit.c:1882 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:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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 *** 2 locks held by syz.2.3820/19503: #0: ffff88802965d940 (&u->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline] #0: ffff88802965d940 (&u->lock){+.+.}-{3:3}, at: queue_oob+0x1d7/0x4e0 net/unix/af_unix.c:2200 #1: ffff888143ae5120 (&f_owner->lock){....}-{3:3}, at: send_sigurg+0x55/0x420 fs/fcntl.c:951 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&dev->event_lock#2){..-.}-{3:3} { IN-SOFTIRQ-W at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0xab/0x320 drivers/input/input.c:418 kd_sound_helper+0x101/0x210 drivers/tty/vt/keyboard.c:256 input_handler_for_each_handle+0xfe/0x1c0 drivers/input/input.c:2554 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers kernel/time/timer.c:2414 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426 run_timer_base kernel/time/timer.c:2435 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 native_irq_enable arch/x86/include/asm/irqflags.h:42 [inline] arch_local_irq_enable arch/x86/include/asm/irqflags.h:119 [inline] raw_spin_rq_unlock_irq kernel/sched/sched.h:1525 [inline] finish_lock_switch kernel/sched/core.c:5130 [inline] finish_task_switch+0x26b/0x950 kernel/sched/core.c:5248 context_switch kernel/sched/core.c:5385 [inline] __schedule+0x16ea/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 __skb_wait_for_more_packets+0x3a2/0x580 net/core/datagram.c:121 __unix_dgram_recvmsg+0x285/0xdc0 net/unix/af_unix.c:2433 sock_recvmsg_nosec net/socket.c:1017 [inline] sock_recvmsg+0x229/0x270 net/socket.c:1039 sock_read_iter+0x231/0x2f0 net/socket.c:1109 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x4cd/0x980 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:713 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:585 [inline] input_inject_event+0xab/0x320 drivers/input/input.c:418 kbd_led_trigger_activate+0xbc/0x100 drivers/tty/vt/keyboard.c:1036 led_trigger_set+0x52a/0x950 drivers/leds/led-triggers.c:212 led_match_default_trigger drivers/leds/led-triggers.c:269 [inline] led_trigger_set_default+0x215/0x250 drivers/leds/led-triggers.c:287 led_classdev_register_ext+0x73d/0x930 drivers/leds/led-class.c:566 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:993 [inline] input_register_device+0xceb/0x10b0 drivers/input/input.c:2412 atkbd_connect+0x70e/0x9c0 drivers/input/keyboard/atkbd.c:1340 serio_connect_driver drivers/input/serio/serio.c:43 [inline] serio_driver_probe+0x7f/0xa0 drivers/input/serio/serio.c:747 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26a/0x9a0 drivers/base/dd.c:657 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:799 driver_probe_device+0x4f/0x430 drivers/base/dd.c:829 __driver_attach+0x452/0x700 drivers/base/dd.c:1215 bus_for_each_dev+0x230/0x2b0 drivers/base/bus.c:370 serio_attach_driver drivers/input/serio/serio.c:776 [inline] serio_handle_event+0x1a2/0x860 drivers/input/serio/serio.c:213 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 } ... key at: [] input_allocate_device.__key.5+0x0/0x20 -> (&client->buffer_lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] evdev_pass_values+0xb9/0xbd0 drivers/input/evdev.c:261 evdev_events+0x1e6/0x340 drivers/input/evdev.c:306 input_pass_values+0x285/0x890 drivers/input/input.c:127 input_event_dispose+0x330/0x6b0 drivers/input/input.c:341 input_inject_event+0x1fe/0x320 drivers/input/input.c:423 evdev_write+0x2fc/0x480 drivers/input/evdev.c:528 vfs_write+0x27b/0xa90 fs/read_write.c:682 ksys_write+0x145/0x250 fs/read_write.c:736 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] evdev_open.__key.25+0x0/0x20 ... acquired at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] evdev_pass_values+0xb9/0xbd0 drivers/input/evdev.c:261 evdev_events+0x1e6/0x340 drivers/input/evdev.c:306 input_pass_values+0x285/0x890 drivers/input/input.c:127 input_event_dispose+0x330/0x6b0 drivers/input/input.c:341 input_inject_event+0x1fe/0x320 drivers/input/input.c:423 evdev_write+0x2fc/0x480 drivers/input/evdev.c:528 vfs_write+0x27b/0xa90 fs/read_write.c:682 ksys_write+0x145/0x250 fs/read_write.c:736 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> (&new->fa_lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:326 fasync_insert_entry+0xc3/0x270 fs/fcntl.c:1048 lease_setup+0x86/0x110 fs/locks.c:573 generic_add_lease fs/locks.c:1874 [inline] generic_setlease+0xd60/0x1240 fs/locks.c:1942 do_fcntl_add_lease fs/locks.c:2047 [inline] fcntl_setlease+0x3a2/0x4c0 fs/locks.c:2069 do_fcntl+0x6a0/0x1910 fs/fcntl.c:536 do_compat_fcntl64+0x484/0x720 fs/fcntl.c:789 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e INITIAL READ USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1124 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1148 fuse_dev_wake_and_unlock fs/fuse/dev.c:332 [inline] fuse_dev_queue_req+0x225/0x2a0 fs/fuse/dev.c:378 __fuse_request_send fs/fuse/dev.c:576 [inline] __fuse_simple_request+0xb15/0x18d0 fs/fuse/dev.c:672 fuse_simple_request fs/fuse/fuse_i.h:1237 [inline] fuse_send_open fs/fuse/file.c:51 [inline] fuse_file_open+0x481/0x910 fs/fuse/file.c:146 fuse_do_open+0x4f/0xc0 fs/fuse/file.c:175 fuse_dir_open+0x110/0x220 fs/fuse/dir.c:1699 do_dentry_open+0xdf0/0x1970 fs/open.c:956 vfs_open+0x3b/0x340 fs/open.c:1086 do_open fs/namei.c:3880 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4039 do_filp_open+0x1fa/0x410 fs/namei.c:4066 do_sys_openat2+0x121/0x1c0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_compat_sys_openat fs/open.c:1506 [inline] __se_compat_sys_openat fs/open.c:1504 [inline] __ia32_compat_sys_openat+0x131/0x160 fs/open.c:1504 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] fasync_insert_entry.__key+0x0/0x20 ... acquired at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:1124 [inline] kill_fasync+0x199/0x4d0 fs/fcntl.c:1148 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values+0x627/0xbd0 drivers/input/evdev.c:278 evdev_events+0x1e6/0x340 drivers/input/evdev.c:306 input_pass_values+0x285/0x890 drivers/input/input.c:127 input_event_dispose+0x330/0x6b0 drivers/input/input.c:341 input_inject_event+0x1fe/0x320 drivers/input/input.c:423 evdev_write+0x2fc/0x480 drivers/input/evdev.c:528 vfs_write+0x27b/0xa90 fs/read_write.c:682 ksys_write+0x145/0x250 fs/read_write.c:736 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> (&f_owner->lock){....}-{3:3} { INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:326 __f_setown+0x67/0x370 fs/fcntl.c:136 generic_add_lease fs/locks.c:1874 [inline] generic_setlease+0xd60/0x1240 fs/locks.c:1942 do_fcntl_add_lease fs/locks.c:2047 [inline] fcntl_setlease+0x3a2/0x4c0 fs/locks.c:2069 do_fcntl+0x6a0/0x1910 fs/fcntl.c:536 do_compat_fcntl64+0x484/0x720 fs/fcntl.c:789 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e INITIAL READ USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_read_lock_irq include/linux/rwlock_api_smp.h:169 [inline] _raw_read_lock_irq+0xaa/0xf0 kernel/locking/spinlock.c:244 f_getown_ex fs/fcntl.c:270 [inline] do_fcntl+0x809/0x1910 fs/fcntl.c:518 do_compat_fcntl64+0x484/0x720 fs/fcntl.c:789 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e } ... key at: [] file_f_owner_allocate.__key+0x0/0x20 ... acquired at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 send_sigio+0x38/0x370 fs/fcntl.c:907 kill_fasync_rcu fs/fcntl.c:1133 [inline] kill_fasync+0x24d/0x4d0 fs/fcntl.c:1148 lease_break_callback+0x26/0x30 fs/locks.c:558 __break_lease+0x6a2/0x1620 fs/locks.c:1592 vfs_truncate+0x428/0x520 fs/open.c:109 do_sys_truncate+0xdb/0x190 fs/open.c:138 __do_compat_sys_truncate fs/open.c:156 [inline] __se_compat_sys_truncate fs/open.c:154 [inline] __ia32_compat_sys_truncate+0x5b/0x70 fs/open.c:154 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 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+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1662 do_wait+0x1f8/0x520 kernel/exit.c:1706 kernel_wait+0xab/0x170 kernel/exit.c:1882 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:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 SOFTIRQ-ON-R at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1662 do_wait+0x1f8/0x520 kernel/exit.c:1706 kernel_wait+0xab/0x170 kernel/exit.c:1882 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:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INITIAL USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:326 copy_process+0x21d5/0x3b80 kernel/fork.c:2561 kernel_clone+0x21e/0x870 kernel/fork.c:2845 user_mode_thread+0xdd/0x140 kernel/fork.c:2923 rest_init+0x23/0x300 init/main.c:708 start_kernel+0x470/0x4f0 init/main.c:1099 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:513 x86_64_start_kernel+0x66/0x70 arch/x86/kernel/head64.c:494 common_startup_64+0x13e/0x147 INITIAL READ USE at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 __do_wait+0xde/0x740 kernel/exit.c:1662 do_wait+0x1f8/0x520 kernel/exit.c:1706 kernel_wait+0xab/0x170 kernel/exit.c:1882 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:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 send_sigurg+0x12b/0x420 fs/fcntl.c:967 sk_send_sigurg+0x6c/0x2e0 net/core/sock.c:3591 queue_oob+0x3d9/0x4e0 net/unix/af_unix.c:2217 unix_stream_sendmsg+0xa41/0xb60 net/unix/af_unix.c:2335 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 ____sys_sendmsg+0x52d/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmmsg+0x28e/0x430 net/socket.c:2702 __compat_sys_sendmmsg net/compat.c:360 [inline] __do_compat_sys_sendmmsg net/compat.c:367 [inline] __se_compat_sys_sendmmsg net/compat.c:364 [inline] __ia32_compat_sys_sendmmsg+0xa2/0xc0 net/compat.c:364 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e stack backtrace: CPU: 0 UID: 0 PID: 19503 Comm: syz.2.3820 Not tainted 6.15.0-rc7-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_bad_irq_dependency kernel/locking/lockdep.c:2652 [inline] check_irq_usage kernel/locking/lockdep.c:2893 [inline] check_prev_add kernel/locking/lockdep.c:3170 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain+0x1f05/0x2140 kernel/locking/lockdep.c:3909 __lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5235 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 send_sigurg+0x12b/0x420 fs/fcntl.c:967 sk_send_sigurg+0x6c/0x2e0 net/core/sock.c:3591 queue_oob+0x3d9/0x4e0 net/unix/af_unix.c:2217 unix_stream_sendmsg+0xa41/0xb60 net/unix/af_unix.c:2335 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 ____sys_sendmsg+0x52d/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmmsg+0x28e/0x430 net/socket.c:2702 __compat_sys_sendmmsg net/compat.c:360 [inline] __do_compat_sys_sendmmsg net/compat.c:367 [inline] __se_compat_sys_sendmmsg net/compat.c:364 [inline] __ia32_compat_sys_sendmmsg+0xa2/0xc0 net/compat.c:364 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/syscall_32.c:306 do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf705e539 Code: 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 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 90 90 RSP: 002b:00000000f504e55c EFLAGS: 00000206 ORIG_RAX: 0000000000000159 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000800010c0 RDX: 0000000000000001 RSI: 0000000004048041 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: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 4: 10 07 adc %al,(%rdi) 6: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi a: 10 08 adc %cl,(%rax) c: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 20: 00 51 52 add %dl,0x52(%rcx) 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: 90 nop 3f: 90 nop