INFO: task syz.2.11410:9983 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.11410 state:D stack:25640 pid:9983 tgid:9983 ppid:8822 task_flags:0x400040 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 request_wait_answer fs/fuse/dev.c:743 [inline] __fuse_request_send fs/fuse/dev.c:757 [inline] fuse_chan_send+0x1065/0x1ac0 fs/fuse/dev.c:833 fuse_simple_request fs/fuse/fuse_i.h:1012 [inline] fuse_flush+0x66e/0x8b0 fs/fuse/file.c:504 filp_flush+0xbd/0x190 fs/open.c:1471 filp_close+0x1d/0x40 fs/open.c:1484 __range_close fs/file.c:793 [inline] __do_sys_close_range fs/file.c:854 [inline] __se_sys_close_range+0x3d3/0x900 fs/file.c:818 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1dd179de59 RSP: 002b:00007f1dd1b4fba8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00007f1dd1a27da0 RCX: 00007f1dd179de59 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f1dd1a27da0 R08: 00007f1dd1a26038 R09: 0000000000000000 R10: 00000000003ffc30 R11: 0000000000000246 R12: 0000000000302b6c R13: 00007f1dd1a2609c R14: 00000000003029ae R15: 00007f1dd1a26090 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by udevd/4990: 2 locks held by getty/5381: #0: ffff8880364910a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:11/16579: #0: ffff888021a9a140 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888021a9a140 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90004bafc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90004bafc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffff88802a6b51d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #2: ffff88802a6b51d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4d30 drivers/usb/core/hub.c:5899 8 locks held by kworker/0:0/750: #0: ffff888021a9a140 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888021a9a140 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc900055f7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc900055f7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffff88802a6291d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #2: ffff88802a6291d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4d30 drivers/usb/core/hub.c:5899 #3: ffff88805345a1d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #3: ffff88805345a1d8 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0xfc/0x9a0 drivers/usb/core/hub.c:2336 #4: ffff88804c9d41a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #4: ffff88804c9d41a0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline] #4: ffff88804c9d41a0 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb9/0x880 drivers/base/dd.c:1369 #5: ffff888059af9a58 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #5: ffff888059af9a58 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline] #5: ffff888059af9a58 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb9/0x880 drivers/base/dd.c:1369 #6: ffffffff8faa4ea0 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline] #6: ffffffff8faa4ea0 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x2d8/0x650 drivers/input/input.c:2204 #7: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #7: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 1 lock held by syz.7.12017/11834: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8082 Comm: kworker/u8:16 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:__asan_memset+0x26/0x50 mm/kasan/shadow.c:87 Code: 90 90 90 90 f3 0f 1e fa 55 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 1e e5 ff ff 84 c0 74 11 <4c> 89 f7 89 ee 48 89 da 5b 41 5e 5d e9 e9 6c 9b 09 31 c0 5b 41 5e RSP: 0018:ffffc90004c3fa18 EFLAGS: 00000202 RAX: ffff88804b7ce001 RBX: 000000000000006c RCX: ffffffff874a81c3 RDX: 0000000000000001 RSI: 000000000000006c RDI: ffff88804b7ce022 RBP: 0000000000000000 R08: ffff88804b7ce08d R09: 1ffff110096f9c11 R10: dffffc0000000000 R11: ffffed10096f9c12 R12: 00000000000000c8 R13: dffffc0000000000 R14: ffff88804b7ce022 R15: ffff888029ca98a8 FS: 0000000000000000(0000) GS:ffff888124f56000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3cff5ed2f8 CR3: 0000000073c0e000 CR4: 00000000003526f0 Call Trace: skb_put_zero include/linux/skbuff.h:2804 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:845 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline] nsim_dev_trap_report_work+0x673/0xb40 drivers/net/netdevsim/dev.c:922 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245