===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected syzkaller #0 Not tainted ----------------------------------------------------- syz.0.6650/24772 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffffffff8ce0a058 (tasklist_lock){.+.+}-{2:2}, at: send_sigurg+0xf0/0x3c0 fs/fcntl.c:827 and this task is already holding: ffff88805a206b18 (&f->f_owner.lock){....}-{2:2}, at: send_sigurg+0x29/0x3c0 fs/fcntl.c:811 which would create a new lock dependency: (&f->f_owner.lock){....}-{2:2} -> (tasklist_lock){.+.+}-{2:2} but this new dependency connects a SOFTIRQ-irq-safe lock: (&client->buffer_lock){..-.}-{2:2} ... which became SOFTIRQ-irq-safe at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __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+0xcb/0xab0 drivers/input/evdev.c:261 evdev_events+0x1d8/0x330 drivers/input/evdev.c:306 input_to_handler drivers/input/input.c:129 [inline] input_pass_values+0x905/0x12f0 drivers/input/input.c:161 input_event_dispose+0x346/0x6c0 drivers/input/input.c:378 input_event+0x8c/0xc0 drivers/input/input.c:435 input_sync include/linux/input.h:450 [inline] hidinput_report_event+0xa1/0xf0 drivers/hid/hid-input.c:1750 hid_report_raw_event+0x151d/0x1750 drivers/hid/hid-core.c:2038 hid_input_report+0x434/0x510 drivers/hid/hid-core.c:2105 hid_irq_in+0x479/0x6d0 drivers/hid/usbhid/hid-core.c:284 __usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1650 dummy_timer+0xc04/0x3080 drivers/usb/gadget/udc/dummy_hcd.c:1993 __run_hrtimer kernel/time/hrtimer.c:1750 [inline] __hrtimer_run_queues+0x520/0xc40 kernel/time/hrtimer.c:1814 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1831 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 lock_acquire+0x208/0x420 kernel/locking/lockdep.c:5758 fs_reclaim_acquire+0x98/0x100 mm/page_alloc.c:3616 might_alloc include/linux/sched/mm.h:303 [inline] slab_pre_alloc_hook+0x2a/0x310 mm/slab.h:714 slab_alloc_node mm/slub.c:3477 [inline] __kmem_cache_alloc_node+0x53/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x230 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] kobject_get_path+0xc3/0x2c0 lib/kobject.c:161 kobject_uevent_env+0x28a/0x8b0 lib/kobject_uevent.c:544 really_probe+0x715/0xb20 drivers/base/dd.c:708 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __device_attach_driver+0x2ca/0x510 drivers/base/dd.c:958 bus_for_each_drv+0x252/0x2e0 drivers/base/bus.c:459 __device_attach+0x2c2/0x420 drivers/base/dd.c:1030 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 hid_add_device+0x38d/0x530 drivers/hid/hid-core.c:2832 usbhid_probe+0xe02/0x1220 drivers/hid/usbhid/hid-core.c:1447 usb_probe_interface+0x5c9/0xb20 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x25b/0xb20 drivers/base/dd.c:658 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __device_attach_driver+0x2ca/0x510 drivers/base/dd.c:958 bus_for_each_drv+0x252/0x2e0 drivers/base/bus.c:459 __device_attach+0x2c2/0x420 drivers/base/dd.c:1030 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 usb_set_configuration+0x1a79/0x20c0 drivers/usb/core/message.c:2207 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:238 usb_probe_device+0x13d/0x270 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x25b/0xb20 drivers/base/dd.c:658 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __device_attach_driver+0x2ca/0x510 drivers/base/dd.c:958 bus_for_each_drv+0x252/0x2e0 drivers/base/bus.c:459 __device_attach+0x2c2/0x420 drivers/base/dd.c:1030 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 usb_new_device+0xa3c/0x1660 drivers/usb/core/hub.c:2660 hub_port_connect drivers/usb/core/hub.c:5529 [inline] hub_port_connect_change drivers/usb/core/hub.c:5669 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x29bf/0x49f0 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 to a SOFTIRQ-irq-unsafe lock: (tasklist_lock){.+.+}-{2:2} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 do_wait+0x294/0xae0 kernel/exit.c:1607 kernel_wait+0xd7/0x1c0 kernel/exit.c:1797 call_usermodehelper_exec_sync kernel/umh.c:137 [inline] call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 other info that might help us debug this: Chain exists of: &client->buffer_lock --> &f->f_owner.lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&client->buffer_lock); lock(&f->f_owner.lock); lock(&client->buffer_lock); *** DEADLOCK *** 2 locks held by syz.0.6650/24772: #0: ffff88807bbe7e80 (&u->lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #0: ffff88807bbe7e80 (&u->lock){+.+.}-{2:2}, at: queue_oob+0x1e2/0x4f0 net/unix/af_unix.c:2190 #1: ffff88805a206b18 (&f->f_owner.lock){....}-{2:2}, at: send_sigurg+0x29/0x3c0 fs/fcntl.c:811 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&client->buffer_lock){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __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+0xcb/0xab0 drivers/input/evdev.c:261 evdev_events+0x1d8/0x330 drivers/input/evdev.c:306 input_to_handler drivers/input/input.c:129 [inline] input_pass_values+0x905/0x12f0 drivers/input/input.c:161 input_event_dispose+0x346/0x6c0 drivers/input/input.c:378 input_event+0x8c/0xc0 drivers/input/input.c:435 input_sync include/linux/input.h:450 [inline] hidinput_report_event+0xa1/0xf0 drivers/hid/hid-input.c:1750 hid_report_raw_event+0x151d/0x1750 drivers/hid/hid-core.c:2038 hid_input_report+0x434/0x510 drivers/hid/hid-core.c:2105 hid_irq_in+0x479/0x6d0 drivers/hid/usbhid/hid-core.c:284 __usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1650 dummy_timer+0xc04/0x3080 drivers/usb/gadget/udc/dummy_hcd.c:1993 __run_hrtimer kernel/time/hrtimer.c:1750 [inline] __hrtimer_run_queues+0x520/0xc40 kernel/time/hrtimer.c:1814 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1831 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 lock_acquire+0x208/0x420 kernel/locking/lockdep.c:5758 fs_reclaim_acquire+0x98/0x100 mm/page_alloc.c:3616 might_alloc include/linux/sched/mm.h:303 [inline] slab_pre_alloc_hook+0x2a/0x310 mm/slab.h:714 slab_alloc_node mm/slub.c:3477 [inline] __kmem_cache_alloc_node+0x53/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x230 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] kobject_get_path+0xc3/0x2c0 lib/kobject.c:161 kobject_uevent_env+0x28a/0x8b0 lib/kobject_uevent.c:544 really_probe+0x715/0xb20 drivers/base/dd.c:708 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __device_attach_driver+0x2ca/0x510 drivers/base/dd.c:958 bus_for_each_drv+0x252/0x2e0 drivers/base/bus.c:459 __device_attach+0x2c2/0x420 drivers/base/dd.c:1030 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 hid_add_device+0x38d/0x530 drivers/hid/hid-core.c:2832 usbhid_probe+0xe02/0x1220 drivers/hid/usbhid/hid-core.c:1447 usb_probe_interface+0x5c9/0xb20 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x25b/0xb20 drivers/base/dd.c:658 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __device_attach_driver+0x2ca/0x510 drivers/base/dd.c:958 bus_for_each_drv+0x252/0x2e0 drivers/base/bus.c:459 __device_attach+0x2c2/0x420 drivers/base/dd.c:1030 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 usb_set_configuration+0x1a79/0x20c0 drivers/usb/core/message.c:2207 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:238 usb_probe_device+0x13d/0x270 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x25b/0xb20 drivers/base/dd.c:658 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830 __device_attach_driver+0x2ca/0x510 drivers/base/dd.c:958 bus_for_each_drv+0x252/0x2e0 drivers/base/bus.c:459 __device_attach+0x2c2/0x420 drivers/base/dd.c:1030 bus_probe_device+0x180/0x260 drivers/base/bus.c:534 device_add+0x85b/0xc20 drivers/base/core.c:3683 usb_new_device+0xa3c/0x1660 drivers/usb/core/hub.c:2660 hub_port_connect drivers/usb/core/hub.c:5529 [inline] hub_port_connect_change drivers/usb/core/hub.c:5669 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x29bf/0x49f0 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 INITIAL USE at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __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+0xcb/0xab0 drivers/input/evdev.c:261 evdev_events+0x1d8/0x330 drivers/input/evdev.c:306 input_to_handler drivers/input/input.c:129 [inline] input_pass_values+0x905/0x12f0 drivers/input/input.c:161 input_event_dispose+0x346/0x6c0 drivers/input/input.c:378 input_inject_event+0x1f9/0x320 drivers/input/input.c:465 evdev_write+0x35f/0x490 drivers/input/evdev.c:530 vfs_write+0x296/0x990 fs/read_write.c:582 ksys_write+0x150/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 } ... key at: [] evdev_open.__key.28+0x0/0x20 -> (&new->fa_lock){....}-{2:2} { INITIAL USE at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xaf/0xf0 kernel/locking/spinlock.c:326 fasync_remove_entry+0xf4/0x1c0 fs/fcntl.c:867 sock_fasync+0x88/0xf0 net/socket.c:1445 __fput+0x7f3/0x970 fs/file_table.c:381 task_work_run+0x1d4/0x260 kernel/task_work.c:245 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 INITIAL READ USE at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xbc/0x100 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:990 [inline] kill_fasync+0x192/0x4b0 fs/fcntl.c:1011 sock_wake_async+0x137/0x160 net/socket.c:-1 sk_wake_async+0x17f/0x280 include/net/sock.h:2615 mptcp_destroy_common+0x113/0x4c0 net/mptcp/protocol.c:3488 mptcp_disconnect+0x204/0x520 net/mptcp/protocol.c:3297 inet_shutdown+0x1be/0x370 net/ipv4/af_inet.c:934 __sys_shutdown_sock net/socket.c:2435 [inline] __sys_shutdown net/socket.c:2447 [inline] __do_sys_shutdown net/socket.c:2455 [inline] __se_sys_shutdown net/socket.c:2453 [inline] __x64_sys_shutdown+0x174/0x1d0 net/socket.c:2453 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 } ... key at: [] fasync_insert_entry.__key+0x0/0x20 ... acquired at: __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xbc/0x100 kernel/locking/spinlock.c:236 kill_fasync_rcu fs/fcntl.c:990 [inline] kill_fasync+0x192/0x4b0 fs/fcntl.c:1011 __pass_event drivers/input/evdev.c:240 [inline] evdev_pass_values+0x54b/0xab0 drivers/input/evdev.c:278 evdev_events+0x1d8/0x330 drivers/input/evdev.c:306 input_to_handler drivers/input/input.c:129 [inline] input_pass_values+0x905/0x12f0 drivers/input/input.c:161 input_event_dispose+0x346/0x6c0 drivers/input/input.c:378 input_inject_event+0x1f9/0x320 drivers/input/input.c:465 evdev_write+0x35f/0x490 drivers/input/evdev.c:530 vfs_write+0x296/0x990 fs/read_write.c:582 ksys_write+0x150/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> (&f->f_owner.lock){....}-{2:2} { INITIAL USE at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xaf/0xf0 kernel/locking/spinlock.c:326 __f_setown+0x3b/0x330 fs/fcntl.c:92 fcntl_dirnotify+0x6e2/0x8d0 fs/notify/dnotify/dnotify.c:369 do_fcntl+0x390/0x1490 fs/fcntl.c:400 __do_sys_fcntl fs/fcntl.c:448 [inline] __se_sys_fcntl+0xc9/0x1a0 fs/fcntl.c:433 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 INITIAL READ USE at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xbc/0x100 kernel/locking/spinlock.c:236 send_sigio+0x33/0x360 fs/fcntl.c:772 kill_fasync_rcu fs/fcntl.c:997 [inline] kill_fasync+0x228/0x4b0 fs/fcntl.c:1011 sock_wake_async+0x137/0x160 net/socket.c:-1 sk_wake_async+0x17f/0x280 include/net/sock.h:2615 mptcp_destroy_common+0x113/0x4c0 net/mptcp/protocol.c:3488 mptcp_disconnect+0x204/0x520 net/mptcp/protocol.c:3297 inet_shutdown+0x1be/0x370 net/ipv4/af_inet.c:934 __sys_shutdown_sock net/socket.c:2435 [inline] __sys_shutdown net/socket.c:2447 [inline] __do_sys_shutdown net/socket.c:2455 [inline] __se_sys_shutdown net/socket.c:2453 [inline] __x64_sys_shutdown+0x174/0x1d0 net/socket.c:2453 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 } ... key at: [] init_file.__key+0x0/0x20 ... acquired at: __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xbc/0x100 kernel/locking/spinlock.c:236 send_sigio+0x33/0x360 fs/fcntl.c:772 kill_fasync_rcu fs/fcntl.c:997 [inline] kill_fasync+0x228/0x4b0 fs/fcntl.c:1011 sock_wake_async+0x137/0x160 net/socket.c:-1 sk_wake_async+0x17f/0x280 include/net/sock.h:2615 mptcp_destroy_common+0x113/0x4c0 net/mptcp/protocol.c:3488 mptcp_disconnect+0x204/0x520 net/mptcp/protocol.c:3297 inet_shutdown+0x1be/0x370 net/ipv4/af_inet.c:934 __sys_shutdown_sock net/socket.c:2435 [inline] __sys_shutdown net/socket.c:2447 [inline] __do_sys_shutdown net/socket.c:2455 [inline] __se_sys_shutdown net/socket.c:2453 [inline] __x64_sys_shutdown+0x174/0x1d0 net/socket.c:2453 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock: -> (tasklist_lock){.+.+}-{2:2} { HARDIRQ-ON-R at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 do_wait+0x294/0xae0 kernel/exit.c:1607 kernel_wait+0xd7/0x1c0 kernel/exit.c:1797 call_usermodehelper_exec_sync kernel/umh.c:137 [inline] call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 SOFTIRQ-ON-R at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 do_wait+0x294/0xae0 kernel/exit.c:1607 kernel_wait+0xd7/0x1c0 kernel/exit.c:1797 call_usermodehelper_exec_sync kernel/umh.c:137 [inline] call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 INITIAL USE at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_write_lock_irq include/linux/rwlock_api_smp.h:195 [inline] _raw_write_lock_irq+0xaf/0xf0 kernel/locking/spinlock.c:326 copy_process+0x2275/0x3d80 kernel/fork.c:2631 kernel_clone+0x24b/0x8a0 kernel/fork.c:2914 user_mode_thread+0x111/0x180 kernel/fork.c:2992 rest_init+0x27/0x300 init/main.c:709 arch_call_rest_init+0xe/0x10 init/main.c:841 start_kernel+0x459/0x4e0 init/main.c:1086 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555 copy_bootdata+0x0/0xe0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x179/0x17b INITIAL READ USE at: lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 do_wait+0x294/0xae0 kernel/exit.c:1607 kernel_wait+0xd7/0x1c0 kernel/exit.c:1797 call_usermodehelper_exec_sync kernel/umh.c:137 [inline] call_usermodehelper_exec_work+0xb9/0x220 kernel/umh.c:164 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 } ... key at: [] tasklist_lock+0x18/0x40 ... acquired at: __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 send_sigurg+0xf0/0x3c0 fs/fcntl.c:827 sk_send_sigurg+0x6f/0xc0 net/core/sock.c:3412 queue_oob+0x3f1/0x4f0 net/unix/af_unix.c:2207 unix_stream_sendmsg+0xaf0/0xbf0 net/unix/af_unix.c:2326 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5ba/0x960 net/socket.c:2594 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2648 __sys_sendmmsg+0x2ca/0x510 net/socket.c:2734 __do_sys_sendmmsg net/socket.c:2763 [inline] __se_sys_sendmmsg net/socket.c:2760 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2760 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 stack backtrace: CPU: 0 PID: 24772 Comm: syz.0.6650 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_bad_irq_dependency kernel/locking/lockdep.c:2626 [inline] check_irq_usage kernel/locking/lockdep.c:2865 [inline] check_prev_add kernel/locking/lockdep.c:3138 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x6851/0x7d40 kernel/locking/lockdep.c:5137 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754 __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline] _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228 send_sigurg+0xf0/0x3c0 fs/fcntl.c:827 sk_send_sigurg+0x6f/0xc0 net/core/sock.c:3412 queue_oob+0x3f1/0x4f0 net/unix/af_unix.c:2207 unix_stream_sendmsg+0xaf0/0xbf0 net/unix/af_unix.c:2326 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5ba/0x960 net/socket.c:2594 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2648 __sys_sendmmsg+0x2ca/0x510 net/socket.c:2734 __do_sys_sendmmsg net/socket.c:2763 [inline] __se_sys_sendmmsg net/socket.c:2760 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2760 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f0c21d9c799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0c22ccf028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f0c22015fa0 RCX: 00007f0c21d9c799 RDX: 0000000000000001 RSI: 0000200000011500 RDI: 0000000000000003 RBP: 00007f0c21e32c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000040015 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0c22016038 R14: 00007f0c22015fa0 R15: 00007ffcff77a058