INFO: task syz.5.801:9295 blocked for more than 143 seconds.
Not tainted 6.16.0-rc4-syzkaller-00324-g1f988d0788f5 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.801 state:D stack:23496 pid:9295 tgid:9295 ppid:7937 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:596
nfsd_umount+0x42/0xd0 fs/nfsd/nfsctl.c:1386
deactivate_locked_super+0xb9/0x130 fs/super.c:474
put_fs_context+0x93/0x790 fs/fs_context.c:520
fscontext_release+0x62/0x80 fs/fsopen.c:73
__fput+0x44c/0xa70 fs/file_table.c:465
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+0xec/0x110 kernel/entry/common.c:114
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f520758e929
RSP: 002b:00007ffe685e74b8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f52077b7ba0 RCX: 00007f520758e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f52077b7ba0 R08: 00000000000001a8 R09: 00000014685e77af
R10: 00000000003ffc34 R11: 0000000000000246 R12: 00000000000856bd
R13: 00007f52077b6080 R14: ffffffffffffffff R15: 00007ffe685e75d0
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by kworker/u8:9/2993:
#0: ffff8881462ce948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff8881462ce948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000b917bc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000b917bc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
1 lock held by acpid/5193:
#0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
2 locks held by getty/5603:
#0: ffff888030c140a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz.0.455/7787:
#0: ffffffff8f571030 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e41bd08 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12a/0x1650 fs/nfsd/nfsctl.c:1922
2 locks held by syz.5.801/9295:
#0: ffff8880489260e0 (&type->s_umount_key#90){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff8880489260e0 (&type->s_umount_key#90){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff8880489260e0 (&type->s_umount_key#90){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffffffff8e41bd08 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:596
4 locks held by syz.8.938/10329:
#0: ffff888034b34dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline]
#0: ffff888034b34dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x510 net/bluetooth/hci_core.c:2717
#1: ffff888034b340b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5282
#2: ffffffff8f672f88 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2068 [inline]
#2: ffffffff8f672f88 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2560
#3: ffff88803380cb38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762
1 lock held by syz.8.1002/10635:
#0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
1 lock held by syz.7.1003/10649:
#0: ffffffff8ef81b28 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:225 [inline]
#0: ffffffff8ef81b28 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x2d8/0x5e0 drivers/input/input.c:2221
5 locks held by dhcpcd-run-hook/10654:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc4-syzkaller-00324-g1f988d0788f5 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 8877 Comm: kworker/u8:13 Not tainted 6.16.0-rc4-syzkaller-00324-g1f988d0788f5 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:__preempt_count_add kernel/rcu/tree.c:741 [inline]
RIP: 0010:rcu_is_watching+0x6/0xb0 kernel/rcu/tree.c:744
Code: e8 cf 23 49 03 eb cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 <41> 56 53 65 ff 05 e0 dd f5 10 e8 6b 1f c1 09 89 c3 83 f8 08 73 65
RSP: 0018:ffffc9001af9f400 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffffffff902fee01 RCX: f81a339c5b9c0300
RDX: ffffc9001af9f501 RSI: ffffffff81729af5 RDI: ffffffff8e13ee20
RBP: dffffc0000000000 R08: ffffc9001af9f598 R09: 0000000000000000
R10: ffffc9001af9f5f8 R11: fffff520035f3ec1 R12: ffffc9001af9f5a8
R13: ffffffff81729af5 R14: ffffffff8e13ee20 R15: ffffffff81729af5
FS: 0000000000000000(0000) GS:ffff888125c50000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055c5a106e078 CR3: 0000000031396000 CR4: 00000000003526f0
Call Trace:
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x4b/0x3e0 kernel/locking/lockdep.c:5882
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2381 [inline]
slab_free mm/slub.c:4643 [inline]
kmem_cache_free+0x18f/0x400 mm/slub.c:4745
nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
nsim_dev_trap_report_work+0x7cf/0xb80 drivers/net/netdevsim/dev.c:851
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245