INFO: task kworker/1:2:938 blocked for more than 143 seconds. Not tainted 6.12.0-rc2-syzkaller-00050-g5b7c893ed5ed #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:2 state:D stack:20144 pid:938 tgid:938 ppid:2 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1843/0x4ae0 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6824 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 adu_disconnect+0xca/0x2b0 drivers/usb/misc/adutux.c:770 usb_unbind_interface+0x25e/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+0x503/0x7c0 drivers/base/dd.c:1296 bus_remove_device+0x34f/0x420 drivers/base/bus.c:576 device_del+0x57a/0x9b0 drivers/base/core.c:3864 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+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 3 locks held by kworker/u8:3/51: 6 locks held by kworker/1:2/938: #0: ffff8880216d2548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff8880216d2548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc90003dffd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90003dffd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffff888027f34190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff888027f34190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5150 drivers/usb/core/hub.c:5849 #3: ffff8880779d1190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff8880779d1190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x103/0x950 drivers/usb/core/hub.c:2295 #4: ffff88806a1b0160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88806a1b0160 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88806a1b0160 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffffffff8f672ea8 (adutux_mutex){+.+.}-{3:3}, at: adu_disconnect+0xca/0x2b0 drivers/usb/misc/adutux.c:770 2 locks held by getty/4984: #0: ffff8880322f20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 6 locks held by kworker/0:5/5278: 1 lock held by syz-executor/5563: #0: ffff88802476e0e0 (&type->s_umount_key#78){+.+.}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88802476e0e0 (&type->s_umount_key#78){+.+.}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88802476e0e0 (&type->s_umount_key#78){+.+.}-{3:3}, at: deactivate_super+0xb5/0xf0 fs/super.c:505 1 lock held by syz.3.1619/10297: #0: ffffffff8f672ea8 (adutux_mutex){+.+.}-{3:3}, at: adu_release+0xbf/0x870 drivers/usb/misc/adutux.c:323 1 lock held by syz.4.2364/13184: #0: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 3 locks held by syz.3.2373/13186: 2 locks held by syz.2.2376/13195: 3 locks held by syz.1.2380/13204: 3 locks held by syz.0.2381/13207: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc2-syzkaller-00050-g5b7c893ed5ed #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 13184 Comm: syz.4.2364 Not tainted 6.12.0-rc2-syzkaller-00050-g5b7c893ed5ed #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline] RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] RIP: 0010:unwind_next_frame+0xb5d/0x22d0 arch/x86/kernel/unwind_orc.c:585 Code: 7c 24 28 49 8d 6d 08 48 89 e8 48 c1 e8 03 48 89 84 24 88 00 00 00 42 80 3c 20 00 74 08 48 89 ef e8 e8 02 ba 00 48 89 6c 24 60 <48> 89 5c 24 40 49 8b 6d 08 49 8d 5d 10 49 89 df 49 c1 ef 03 43 80 RSP: 0018:ffffc90004b5ec70 EFLAGS: 00000246 RAX: 1ffff9200096bda9 RBX: 1ffffffff215f725 RCX: ffffffff9035c5dc RDX: ffffffff90afb92a RSI: 0000000000000002 RDI: ffffffff814166e0 RBP: ffffc90004b5ed48 R08: 0000000000000003 R09: ffffc90004b5ee30 R10: ffffc90004b5ed90 R11: ffffffff81809fb0 R12: dffffc0000000000 R13: ffffc90004b5ed40 R14: ffffc90004b5ed78 R15: ffffffff90afb92e FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff1f0067d60 CR3: 0000000011c94000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 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+0x135/0x2a0 mm/slub.c:4141 fill_pool lib/debugobjects.c:168 [inline] debug_objects_fill_pool+0x617/0x9f0 lib/debugobjects.c:615 debug_object_activate+0x135/0x510 lib/debugobjects.c:704 debug_rcu_head_queue kernel/rcu/rcu.h:224 [inline] __call_rcu_common kernel/rcu/tree.c:3071 [inline] call_rcu+0x97/0xa70 kernel/rcu/tree.c:3190 destroy_inode fs/inode.c:318 [inline] evict+0x83c/0x9b0 fs/inode.c:754 __dentry_kill+0x20d/0x630 fs/dcache.c:615 shrink_kill+0xa9/0x2c0 fs/dcache.c:1060 shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1087 shrink_dcache_parent+0xcb/0x3b0 do_one_tree+0x23/0xe0 fs/dcache.c:1550 shrink_dcache_for_umount+0xb4/0x180 fs/dcache.c:1567 generic_shutdown_super+0x6a/0x2d0 fs/super.c:620 kill_anon_super fs/super.c:1237 [inline] kill_litter_super+0x76/0xb0 fs/super.c:1247 deactivate_locked_super+0xc4/0x130 fs/super.c:473 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373 task_work_run+0x24f/0x310 kernel/task_work.c:228 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:939 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 get_signal+0x16a3/0x1740 kernel/signal.c:2917 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [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+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcb4657c990 Code: Unable to access opcode bytes at 0x7fcb4657c966. RSP: 002b:00007fcb47371b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: fffffffffffffffc RBX: 0000000000000002 RCX: 00007fcb4657c990 RDX: 0000000000000002 RSI: 00007fcb47371c10 RDI: 00000000ffffff9c RBP: 00007fcb47371c10 R08: 0000000000000000 R09: 00007fcb47371987 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fcb46736058 R15: 00007ffd186f7588