INFO: task syz.7.731:9137 blocked for more than 144 seconds. Not tainted 6.12.0-rc7-syzkaller-00189-ge8bdb3c8be08 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.731 state:D stack:27024 pid:9137 tgid:9135 ppid:8391 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6693 __schedule_loop kernel/sched/core.c:6770 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6785 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6842 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:815 [inline] open_last_lookups fs/namei.c:3691 [inline] path_openat+0x89a/0x3590 fs/namei.c:3930 do_filp_open+0x235/0x490 fs/namei.c:3960 do_sys_openat2+0x13e/0x1d0 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+0x247/0x2a0 fs/open.c:1441 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f50ff37e719 RSP: 002b:00007f50fd7d5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f50ff536058 RCX: 00007f50ff37e719 RDX: 000000000000275a RSI: 0000000020000140 RDI: ffffffffffffff9c RBP: 00007f50ff3f175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f50ff536058 R15: 00007ffc42e828f8 INFO: task syz.7.731:9140 blocked for more than 144 seconds. Not tainted 6.12.0-rc7-syzkaller-00189-ge8bdb3c8be08 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.731 state:D stack:25216 pid:9140 tgid:9135 ppid:8391 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6693 __schedule_loop kernel/sched/core.c:6770 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6785 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6842 rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1d7/0x220 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:815 [inline] open_last_lookups fs/namei.c:3691 [inline] path_openat+0x89a/0x3590 fs/namei.c:3930 do_filp_open+0x235/0x490 fs/namei.c:3960 do_sys_openat2+0x13e/0x1d0 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+0x247/0x2a0 fs/open.c:1441 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f50ff37e719 RSP: 002b:00007f50fd7b4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f50ff536130 RCX: 00007f50ff37e719 RDX: 000000000000275a RSI: 0000000020000100 RDI: ffffffffffffff9c RBP: 00007f50ff3f175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f50ff536130 R15: 00007ffc42e828f8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 4 locks held by kworker/u8:5/1084: 2 locks held by getty/5595: #0: ffff88814d22c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:7/5910: #0: ffff88801ac78948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac78948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc9000304fd00 (key_gc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000304fd00 (key_gc_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #2: ffffffff8e93d338 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 6 locks held by kworker/1:8/5978: #0: ffff88801eeb2148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801eeb2148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900040e7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900040e7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff888144b03190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff888144b03190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5150 drivers/usb/core/hub.c:5849 #3: ffff888144b06510 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3206 [inline] #3: ffff888144b06510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5418 [inline] #3: ffff888144b06510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] #3: ffff888144b06510 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5821 [inline] #3: ffff888144b06510 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x25b9/0x5150 drivers/usb/core/hub.c:5903 #4: ffff88802615e468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5419 [inline] #4: ffff88802615e468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] #4: ffff88802615e468 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5821 [inline] #4: ffff88802615e468 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x25f7/0x5150 drivers/usb/core/hub.c:5903 #5: ffff8880b873ea98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598 2 locks held by syz.7.731/9136: 2 locks held by syz.7.731/9137: #0: ffff8880596c2420 (sb_writers#37){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88804c7a8180 (&type->i_mutex_dir_key#23){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff88804c7a8180 (&type->i_mutex_dir_key#23){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3691 [inline] #1: ffff88804c7a8180 (&type->i_mutex_dir_key#23){+.+.}-{3:3}, at: path_openat+0x89a/0x3590 fs/namei.c:3930 2 locks held by syz.7.731/9140: #0: ffff8880596c2420 (sb_writers#37){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 #1: ffff88804c7a8180 (&type->i_mutex_dir_key#23){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #1: ffff88804c7a8180 (&type->i_mutex_dir_key#23){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3691 [inline] #1: ffff88804c7a8180 (&type->i_mutex_dir_key#23){+.+.}-{3:3}, at: path_openat+0x89a/0x3590 fs/namei.c:3930 4 locks held by syz.2.1075/10674: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc7-syzkaller-00189-ge8bdb3c8be08 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5901 Comm: kworker/0:4 Not tainted 6.12.0-rc7-syzkaller-00189-ge8bdb3c8be08 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Workqueue: usb_hub_wq hub_event RIP: 0010:__bfs_next kernel/locking/lockdep.c:1695 [inline] RIP: 0010:__bfs kernel/locking/lockdep.c:1748 [inline] RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1856 [inline] RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2827 [inline] RIP: 0010:check_prev_add kernel/locking/lockdep.c:3165 [inline] RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3280 [inline] RIP: 0010:validate_chain+0x1c42/0x5920 kernel/locking/lockdep.c:3904 Code: 00 00 00 45 31 ed eb 08 85 c0 0f 84 00 03 00 00 4d 85 ed 49 bc 00 00 00 00 00 fc ff df 0f 84 aa 00 00 00 49 8d 5d 30 48 89 d8 <48> c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 db 9a 8d 00 48 8b 1b RSP: 0018:ffffc90004246820 EFLAGS: 00000086 RAX: ffffffff96daf508 RBX: ffffffff96daf508 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffc90004246940 RBP: ffffc90004246b20 R08: ffffffff942d0817 R09: 1ffffffff285a102 R10: dffffc0000000000 R11: fffffbfff285a103 R12: dffffc0000000000 R13: ffffffff96daf4d8 R14: ffffffff96daf4e8 R15: 1ffffffff279d3a4 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f651fd08ab8 CR3: 000000005fe02000 CR4: 0000000000350ef0 Call Trace: __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598 raw_spin_rq_lock kernel/sched/sched.h:1506 [inline] rq_lock kernel/sched/sched.h:1805 [inline] ttwu_queue kernel/sched/core.c:3951 [inline] try_to_wake_up+0x81e/0x14b0 kernel/sched/core.c:4281 devtmpfs_submit_req drivers/base/devtmpfs.c:106 [inline] devtmpfs_delete_node+0x20d/0x300 drivers/base/devtmpfs.c:156 device_del+0x332/0x9b0 drivers/base/core.c:3840 snd_unregister_device+0x14e/0x1a0 sound/core/sound.c:309 snd_rawmidi_dev_disconnect+0x4b8/0x630 sound/core/rawmidi.c:2076 __snd_device_disconnect sound/core/device.c:63 [inline] snd_device_disconnect_all+0xcc/0x1f0 sound/core/device.c:215 snd_card_disconnect+0x3ca/0x830 sound/core/init.c:534 usb_audio_disconnect+0x263/0x710 sound/usb/card.c:972 usb_unbind_interface+0x260/0x940 drivers/usb/core/driver.c:461 device_remove drivers/base/dd.c:569 [inline] __device_release_driver drivers/base/dd.c:1273 [inline] device_release_driver_internal+0x505/0x7c0 drivers/base/dd.c:1296 bus_remove_device+0x34f/0x420 drivers/base/bus.c:576 device_del+0x57a/0x9b0 drivers/base/core.c:3861 usb_disable_device+0x3bf/0x850 drivers/usb/core/message.c:1418 usb_disconnect+0x340/0x950 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+0x1ebc/0x5150 drivers/usb/core/hub.c:5903 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244