Hello, syzbot has tested the proposed patch but the reproducer is still triggering an issue: INFO: task hung in usb_deregister_dev INFO: task kworker/1:0:24 blocked for more than 143 seconds. Not tainted 6.12.0-rc3-syzkaller-dirty #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:0 state:D stack:23808 pid:24 tgid:24 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> context_switch kernel/sched/core.c:5322 [inline] __schedule+0x105f/0x34b0 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831 rwsem_down_write_slowpath+0x539/0x12a0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1d8/0x200 kernel/locking/rwsem.c:1578 usb_deregister_dev+0x7c/0x1e0 drivers/usb/core/file.c:186 wdm_disconnect+0x25/0x440 drivers/usb/class/cdc-wdm.c:1214 usb_unbind_interface+0x1e8/0x970 drivers/usb/core/driver.c:461 device_remove drivers/base/dd.c:569 [inline] device_remove+0x122/0x170 drivers/base/dd.c:561 __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1296 bus_remove_device+0x22f/0x420 drivers/base/bus.c:576 device_del+0x396/0x9f0 drivers/base/core.c:3864 usb_disable_device+0x36c/0x7f0 drivers/usb/core/message.c:1418 usb_disconnect+0x2e1/0x920 drivers/usb/core/hub.c:2304 hub_port_connect drivers/usb/core/hub.c:5361 [inline] hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] port_event drivers/usb/core/hub.c:5821 [inline] hub_event+0x1bed/0x4f40 drivers/usb/core/hub.c:5903 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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 </TASK> INFO: task kworker/1:1:36 blocked for more than 143 seconds. Not tainted 6.12.0-rc3-syzkaller-dirty #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:1 state:D stack:24144 pid:36 tgid:36 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> context_switch kernel/sched/core.c:5322 [inline] __schedule+0x105f/0x34b0 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831 rwsem_down_write_slowpath+0x539/0x12a0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1d8/0x200 kernel/locking/rwsem.c:1578 usb_deregister_dev+0x7c/0x1e0 drivers/usb/core/file.c:186 wdm_disconnect+0x25/0x440 drivers/usb/class/cdc-wdm.c:1214 usb_unbind_interface+0x1e8/0x970 drivers/usb/core/driver.c:461 device_remove drivers/base/dd.c:569 [inline] device_remove+0x122/0x170 drivers/base/dd.c:561 __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1296 bus_remove_device+0x22f/0x420 drivers/base/bus.c:576 device_del+0x396/0x9f0 drivers/base/core.c:3864 usb_disable_device+0x36c/0x7f0 drivers/usb/core/message.c:1418 usb_disconnect+0x2e1/0x920 drivers/usb/core/hub.c:2304 hub_port_connect drivers/usb/core/hub.c:5361 [inline] hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] port_event drivers/usb/core/hub.c:5821 [inline] hub_event+0x1bed/0x4f40 drivers/usb/core/hub.c:5903 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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 </TASK> INFO: task kworker/1:3:6534 blocked for more than 144 seconds. Not tainted 6.12.0-rc3-syzkaller-dirty #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:3 state:D stack:23808 pid:6534 tgid:6534 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: <TASK> context_switch kernel/sched/core.c:5322 [inline] __schedule+0x105f/0x34b0 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831 rwsem_down_write_slowpath+0x539/0x12a0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1d8/0x200 kernel/locking/rwsem.c:1578 usb_register_dev+0x11c/0x550 drivers/usb/core/file.c:134 wdm_create+0x1269/0x1870 drivers/usb/class/cdc-wdm.c:1113 wdm_probe+0x239/0x2e0 drivers/usb/class/cdc-wdm.c:1165 usb_probe_interface+0x309/0x9d0 drivers/usb/core/driver.c:399 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:658 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:800 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:958 bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:459 __device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:534 device_add+0x114b/0x1a70 drivers/base/core.c:3675 usb_set_configuration+0x10cb/0x1c50 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:254 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:294 call_driver_probe drivers/base/dd.c:579 [inline] really_probe+0x23e/0xa90 drivers/base/dd.c:658 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:800 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:958 bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:459 __device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:534 device_add+0x114b/0x1a70 drivers/base/core.c:3675 usb_new_device+0xd90/0x1a10 drivers/usb/core/hub.c:2651 hub_port_connect drivers/usb/core/hub.c:5521 [inline] hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] port_event drivers/usb/core/hub.c:5821 [inline] hub_event+0x2e58/0x4f40 drivers/usb/core/hub.c:5903 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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 </TASK> INFO: task kworker/1:4:6535 blocked for more than 144 seconds. Not tainted 6.12.0-rc3-syzkaller-dirty #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:4 state:D stack:23808 pid:6535 tgid:6535 ppid:2 flags:0x00004000 Workqueue: pm pm_runtime_work Call Trace: <TASK> context_switch kernel/sched/core.c:5322 [inline] __schedule+0x105f/0x34b0 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6774 usb_kill_urb.part.0+0x1ca/0x250 drivers/usb/core/urb.c:713 usb_kill_urb+0x83/0xa0 drivers/usb/core/urb.c:702 usb_start_wait_urb+0x255/0x4c0 drivers/usb/core/message.c:65 usb_internal_control_msg drivers/usb/core/message.c:103 [inline] usb_control_msg+0x327/0x4b0 drivers/usb/core/message.c:154 usb_enable_remote_wakeup drivers/usb/core/hub.c:3365 [inline] usb_port_suspend+0x339/0xf10 drivers/usb/core/hub.c:3472 usb_generic_driver_suspend+0xeb/0x1d0 drivers/usb/core/generic.c:302 usb_suspend_device drivers/usb/core/driver.c:1272 [inline] usb_suspend_both+0x66d/0x9c0 drivers/usb/core/driver.c:1443 usb_runtime_suspend+0x49/0x180 drivers/usb/core/driver.c:1968 __rpm_callback+0xc5/0x4c0 drivers/base/power/runtime.c:394 rpm_callback+0x192/0x1d0 drivers/base/power/runtime.c:448 rpm_suspend+0x2e7/0x1200 drivers/base/power/runtime.c:672 __pm_runtime_suspend+0xbc/0x160 drivers/base/power/runtime.c:1142 pm_runtime_autosuspend include/linux/pm_runtime.h:342 [inline] usb_runtime_idle+0x4c/0x60 drivers/usb/core/driver.c:2005 rpm_idle+0x2f7/0x740 drivers/base/power/runtime.c:524 pm_runtime_work+0x120/0x150 drivers/base/power/runtime.c:970 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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 </TASK> INFO: task syz.4.93:6688 blocked for more than 144 seconds. Not tainted 6.12.0-rc3-syzkaller-dirty #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.93 state:D stack:27856 pid:6688 tgid:6688 ppid:4261 flags:0x00000004 Call Trace: <TASK> context_switch kernel/sched/core.c:5322 [inline] __schedule+0x105f/0x34b0 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 wdm_release+0x4b/0x440 drivers/usb/class/cdc-wdm.c:764 __fput+0x3f6/0xb60 fs/file_table.c:431 task_work_run+0x14e/0x250 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x24e/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: 0033:0x7ff46cc3dff9 RSP: 002b:00007fffd3498058 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 000000000002232c RCX: 00007ff46cc3dff9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007ff46cdf7a80 R08: 0000000000000001 R09: 00007fffd349834f R10: 00007ff46cac0000 R11: 0000000000000246 R12: 00000000000226cf R13: 00007fffd3498160 R14: 0000000000000032 R15: ffffffffffffffff </TASK> INFO: task syz.0.94:6692 blocked for more than 145 seconds. Not tainted 6.12.0-rc3-syzkaller-dirty #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.94 state:D stack:27120 pid:6692 tgid:6691 ppid:4250 flags:0x00004004 Call Trace: <TASK> context_switch kernel/sched/core.c:5322 [inline] __schedule+0x105f/0x34b0 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6774 rpm_resume+0x5a8/0x1330 drivers/base/power/runtime.c:834 rpm_resume+0x750/0x1330 drivers/base/power/runtime.c:892 __pm_runtime_resume+0xb6/0x170 drivers/base/power/runtime.c:1172 pm_runtime_resume_and_get include/linux/pm_runtime.h:430 [inline] usb_autopm_get_interface+0x20/0xe0 drivers/usb/core/driver.c:1833 wdm_open+0x24a/0x630 drivers/usb/class/cdc-wdm.c:730 usb_open+0x186/0x220 drivers/usb/core/file.c:47 chrdev_open+0x237/0x6a0 fs/char_dev.c:414 do_dentry_open+0x6cb/0x1390 fs/open.c:958 vfs_open+0x82/0x3f0 fs/open.c:1088 do_open fs/namei.c:3774 [inline] path_openat+0x1e6a/0x2d60 fs/namei.c:3933 do_filp_open+0x1dc/0x430 fs/namei.c:3960 do_sys_openat2+0x17a/0x1e0 fs/open.c:1415 do_sys_open fs/open.c:1430 [inline] __do_sys_openat fs/open.c:1446 [inline] __se_sys_openat fs/open.c:1441 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1441 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: 0033:0x7f264e65c990 RSP: 002b:00007f264e0d8b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f264e65c990 RDX: 0000000000000002 RSI: 00007f264e0d8c10 RDI: 00000000ffffff9c RBP: 00007f264e0d8c10 R08: 0000000000000000 R09: 00007f264e0d8987 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f264e815f80 R15: 00007ffe0b725c08 </TASK> INFO: task syz.1.95:6694 blocked for more than 145 seconds. Not tainted 6.12.0-rc3-syzkaller-dirty #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.95 state:D stack:28432 pid:6694 tgid:6693 ppid:4257 flags:0x00000004 Call Trace: <TASK> context_switch kernel/sched/core.c:5322 [inline] __schedule+0x105f/0x34b0 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831 rwsem_down_read_slowpath+0x61e/0xb20 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x124/0x330 kernel/locking/rwsem.c:1526 usb_open+0x23/0x220 drivers/usb/core/file.c:38 chrdev_open+0x237/0x6a0 fs/char_dev.c:414 do_dentry_open+0x6cb/0x1390 fs/open.c:958 vfs_open+0x82/0x3f0 fs/open.c:1088 do_open fs/namei.c:3774 [inline] path_openat+0x1e6a/0x2d60 fs/namei.c:3933 do_filp_open+0x1dc/0x430 fs/namei.c:3960 do_sys_openat2+0x17a/0x1e0 fs/open.c:1415 do_sys_open fs/open.c:1430 [inline] __do_sys_openat fs/open.c:1446 [inline] __se_sys_openat fs/open.c:1441 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1441 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: 0033:0x7fbe0b20c990 RSP: 002b:00007fbe0ac8eb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fbe0b20c990 RDX: 0000000000000002 RSI: 00007fbe0ac8ec10 RDI: 00000000ffffff9c RBP: 00007fbe0ac8ec10 R08: 0000000000000000 R09: 00007fbe0ac8e987 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbe0b3c5f80 R15: 00007ffe707cfc08 </TASK> Showing all locks held in the system: 6 locks held by kworker/1:0/24: #0: ffff888106299d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc9000019fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff888109785190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff888109785190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff888105ecf190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff888105ecf190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2295 #4: ffff888105ede160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff888105ede160 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff888105ede160 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1293 #5: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_deregister_dev+0x7c/0x1e0 drivers/usb/core/file.c:186 1 lock held by khungtaskd/30: #0: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff88ebb100 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720 6 locks held by kworker/1:1/36: #0: ffff888106299d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90000267d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff8881097a5190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff8881097a5190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff88812e7bc190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff88812e7bc190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2295 #4: ffff888131992160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff888131992160 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff888131992160 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1293 #5: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_deregister_dev+0x7c/0x1e0 drivers/usb/core/file.c:186 2 locks held by kworker/u8:3/46: #0: ffff888100089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90000517d80 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 2 locks held by getty/2606: #0: ffff88810f73f0a0 (&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 2 locks held by kworker/u8:7/4832: #0: ffff888100089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90002a3fd80 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 6 locks held by kworker/1:3/6534: #0: ffff888106299d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90001bdfd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff888109735190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff888109735190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff888100fc7190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff888100fc7190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff888100fc1160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff888100fc1160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_register_dev+0x11c/0x550 drivers/usb/core/file.c:134 3 locks held by kworker/1:4/6535: #0: ffff8881026e8548 ((wq_completion)pm){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90001bcfd80 ((work_completion)(&dev->power.work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff888109b38508 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3206 [inline] #2: ffff888109b38508 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_port_suspend+0x255/0xf10 drivers/usb/core/hub.c:3463 1 lock held by syz.4.93/6688: #0: ffffffff89a968c8 (wdm_mutex){+.+.}-{3:3}, at: wdm_release+0x4b/0x440 drivers/usb/class/cdc-wdm.c:764 2 locks held by syz.0.94/6692: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 #1: ffffffff89a968c8 (wdm_mutex){+.+.}-{3:3}, at: wdm_open+0x5d/0x630 drivers/usb/class/cdc-wdm.c:715 1 lock held by syz.1.95/6694: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.4.104/8014: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.0.102/8025: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.1.106/8099: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.4.125/9473: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.0.123/9479: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.1.127/9504: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.0.146/10885: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.4.148/10909: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.1.147/10912: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.1.168/12230: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.4.169/12276: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.0.167/12316: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.1.188/13565: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.4.190/13705: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.0.191/13720: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 1 lock held by syz.1.209/14857: #0: ffffffff899dae90 (minor_rwsem){++++}-{3:3}, at: usb_open+0x23/0x220 drivers/usb/core/file.c:38 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc3-syzkaller-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 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 </TASK> Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 14907 Comm: modprobe Not tainted 6.12.0-rc3-syzkaller-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:stack_access_ok+0xc/0x200 arch/x86/kernel/unwind_orc.c:389 Code: ff e9 b0 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 b8 00 00 00 00 00 fc ff df 41 57 <41> 56 4c 8d 77 08 41 55 41 54 49 89 d4 4c 89 f2 55 48 c1 ea 03 48 RSP: 0018:ffffc9000564e6e8 EFLAGS: 00000287 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff8aba1902 RDX: 0000000000000008 RSI: ffffc9000564fd60 RDI: ffffc9000564e768 RBP: ffffc9000564fd60 R08: 0000000000000001 R09: ffffffff8aba1906 R10: ffffc9000564e768 R11: 0000000000009eb0 R12: ffffc9000564e7b8 R13: ffffc9000564e768 R14: ffffc9000564fd90 R15: ffffc9000564fd88 FS: 0000000000000000(0000) GS:ffff8881f5800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f40557b3020 CR3: 00000001171fc000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] unwind_next_frame+0x15dd/0x20c0 arch/x86/kernel/unwind_orc.c:648 arch_stack_walk+0x95/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6e/0x70 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] kmem_cache_alloc_noprof+0x11c/0x2b0 mm/slub.c:4141 fill_pool+0x11c/0x5c0 lib/debugobjects.c:168 debug_objects_fill_pool lib/debugobjects.c:615 [inline] debug_object_activate+0x151/0x540 lib/debugobjects.c:704 debug_rcu_head_queue kernel/rcu/rcu.h:224 [inline] __call_rcu_common.constprop.0+0x2c/0x7a0 kernel/rcu/tree.c:3071 mas_free lib/maple_tree.c:1303 [inline] mas_topiary_replace+0x2a84/0x3620 lib/maple_tree.c:2586 mas_wmb_replace lib/maple_tree.c:2643 [inline] mas_split+0x99e/0x10b0 lib/maple_tree.c:3373 mas_commit_b_node.isra.0+0x76/0xb0 lib/maple_tree.c:3393 mas_wr_bnode+0x156/0x1e0 lib/maple_tree.c:4044 mas_wr_store_entry+0x9c7/0x30e0 lib/maple_tree.c:4085 mas_store_prealloc+0x77e/0x1690 lib/maple_tree.c:5520 mmap_region+0x16b5/0x2900 mm/mmap.c:1513 do_mmap+0xc00/0xfc0 mm/mmap.c:496 vm_mmap_pgoff+0x1ba/0x350 mm/util.c:588 ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:542 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:79 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:79 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: 0033:0x7f40557d0b74 Code: 63 08 44 89 e8 5b 41 5c 41 5d c3 41 89 ca 41 f7 c1 ff 0f 00 00 74 0c c7 05 f5 46 01 00 16 00 00 00 eb 17 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 0c f7 d8 89 05 dc 46 01 00 48 83 c8 ff c3 0f RSP: 002b:00007ffeffcbd918 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00000000000000a0 RCX: 00007f40557d0b74 RDX: 0000000000000003 RSI: 0000000000002000 RDI: 0000000000000000 RBP: 0000000000002000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000002 R14: 0000000000000000 R15: 00007f40557e52a0 </TASK> Tested on: commit: 8e929cb5 Linux 6.12-rc3 git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git v6.12-rc3 console output: https://syzkaller.appspot.com/x/log.txt?x=106f5887980000 kernel config: https://syzkaller.appspot.com/x/.config?x=9878fe11046ea2c6 dashboard link: https://syzkaller.appspot.com/bug?extid=f342ea16c9d06d80b585 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 patch: https://syzkaller.appspot.com/x/patch.diff?x=10375887980000