INFO: task syz-executor:5865 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:19496 pid:5865 tgid:5865 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7046 [inline] schedule+0x165/0x360 kernel/sched/core.c:7061 netfs_wait_for_outstanding_io include/linux/netfs.h:552 [inline] v9fs_evict_inode+0x170/0x320 fs/9p/vfs_inode.c:348 evict+0x504/0x9c0 fs/inode.c:810 dispose_list fs/inode.c:852 [inline] evict_inodes+0x64c/0x6d0 fs/inode.c:906 generic_shutdown_super+0x9a/0x2c0 fs/super.c:627 kill_anon_super+0x3b/0x70 fs/super.c:1281 v9fs_kill_super+0x4c/0x90 fs/9p/vfs_super.c:195 deactivate_locked_super+0xbc/0x130 fs/super.c:473 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1327 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f90d258fed7 RSP: 002b:00007ffc60e6a9b8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f90d2611c05 RCX: 00007f90d258fed7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc60e6aa70 RBP: 00007ffc60e6aa70 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000206 R12: 00007ffc60e6bb00 R13: 00007f90d2611c05 R14: 0000000000014f53 R15: 00007ffc60e6bb40 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e53d360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e53d360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e53d360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5627: #0: ffff88814d4350a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5865: #0: ffff8880708940e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880708940e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880708940e0 (&type->s_umount_key#54){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 6 locks held by kworker/1:4/5913: #0: ffff888020ed1548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888020ed1548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90004517ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90004517ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff8881457c1198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline] #2: ffff8881457c1198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898 #3: ffff8881457c4518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3251 [inline] #3: ffff8881457c4518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5463 [inline] #3: ffff8881457c4518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #3: ffff8881457c4518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline] #3: ffff8881457c4518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b8/0x4a20 drivers/usb/core/hub.c:5952 #4: ffff8881437e9b68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline] #4: ffff8881437e9b68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] #4: ffff8881437e9b68 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline] #4: ffff8881437e9b68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21e5/0x4a20 drivers/usb/core/hub.c:5952 #5: ffff8880b873a018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636 1 lock held by syz.2.227/6785: #0: ffff8880708940e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880708940e0 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz.3.243/6836: #0: ffff8880708940e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880708940e0 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz.3.243/6838: #0: ffff8880708940e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880708940e0 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5913 Comm: kworker/1:4 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:mark_lock+0xa0/0x190 kernel/locking/lockdep.c:4774 Code: c7 c7 ad 95 e9 8d 48 c7 c6 7b c1 d8 8d e8 c8 9c e5 ff 90 0f 0b 90 90 90 31 c9 4c 89 fe 4c 89 f7 b8 01 00 00 00 85 69 60 74 10 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 91 06 f1 09 cc 49 89 fe 49 89 f7 RSP: 0018:ffffc90000a08a98 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff93910330 RDX: 0000000000000000 RSI: ffff888078c42a10 RDI: ffff888078c41e40 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff84dd60ca R10: ffffc90000a08cb0 R11: fffff52000141198 R12: 0000000000000002 R13: 0000000000000002 R14: ffff888078c42a10 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88812589c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f17bfd71fe0 CR3: 00000000269e6000 CR4: 00000000003526f0 Call Trace: mark_usage kernel/locking/lockdep.c:4639 [inline] __lock_acquire+0x65a/0xd20 kernel/locking/lockdep.c:5191 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 debug_object_deactivate+0x9a/0x250 lib/debugobjects.c:873 debug_hrtimer_deactivate kernel/time/hrtimer.c:443 [inline] debug_deactivate+0x1d/0x200 kernel/time/hrtimer.c:483 __run_hrtimer kernel/time/hrtimer.c:1745 [inline] __hrtimer_run_queues+0x2b0/0xc60 kernel/time/hrtimer.c:1841 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2034 [inline] RIP: 0010:vprintk_emit+0x49d/0x590 kernel/printk/printk.c:2422 Code: 0f 84 34 ff ff ff e8 12 9b 1f 00 fb eb 44 e8 0a 9b 1f 00 e8 75 90 eb 09 4d 85 f6 74 94 e8 fb 9a 1f 00 fb 48 c7 c7 80 13 53 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 6b 3b RSP: 0018:ffffc900045172a0 EFLAGS: 00000287 RAX: ffffffff81a081a5 RBX: ffffffff81a07ffe RCX: 0000000000100000 RDX: ffffc90016322000 RSI: 00000000000165bf RDI: ffffffff8e531380 RBP: ffffc900045173b0 R08: ffffffff8fe58337 R09: 1ffffffff1fcb066 R10: dffffc0000000000 R11: fffffbfff1fcb067 R12: 0000000000000000 R13: 0000000000000029 R14: 0000000000000200 R15: 1ffff920008a2e58 dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4914 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4925 _dev_info+0x10a/0x160 drivers/base/core.c:4983 usb_disconnect+0xdd/0x950 drivers/usb/core/hub.c:2326 hub_port_connect drivers/usb/core/hub.c:5406 [inline] hub_port_connect_change drivers/usb/core/hub.c:5706 [inline] port_event drivers/usb/core/hub.c:5870 [inline] hub_event+0x1cf5/0x4a20 drivers/usb/core/hub.c:5952 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245