INFO: task syz-executor:5986 blocked for more than 143 seconds.
Not tainted 6.14.0-rc6-syzkaller-00007-g0b46b049d6ec #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:20544 pid:5986 tgid:5986 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0x18bc/0x4c40 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6857
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
__mutex_lock_common kernel/locking/mutex.c:662 [inline]
__mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730
nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:596
nfsd_umount+0x43/0xd0 fs/nfsd/nfsctl.c:1386
deactivate_locked_super+0xc4/0x130 fs/super.c:473
cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1413
task_work_run+0x24f/0x310 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fba8dd8e497
RSP: 002b:00007fff3751a538 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fba8de0e08c RCX: 00007fba8dd8e497
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff3751a5f0
RBP: 00007fff3751a5f0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff3751b680
R13: 00007fba8de0e08c R14: 00000000000ea647 R15: 00007fff3751b6c0
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
3 locks held by kworker/u8:5/266:
2 locks held by getty/5574:
#0: ffff88814d7830a0 (&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+0x616/0x1770 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5986:
#0: ffff888040ad60e0 (&type->s_umount_key#103){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff888040ad60e0 (&type->s_umount_key#103){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff888040ad60e0 (&type->s_umount_key#103){++++}-{4:4}, at: deactivate_super+0xb5/0xf0 fs/super.c:505
#1: ffffffff8ee05a48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:596
2 locks held by kworker/u8:2/11583:
2 locks held by syz.6.14988/12862:
#0: ffffffff8ff27b50 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ee05a48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x12d/0x1a90 fs/nfsd/nfsctl.c:1922
2 locks held by syz-executor/13548:
#0: ffffffff8fec3a48 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8fec3a48 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517
#1: ffffffff8eb3e8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:302 [inline]
#1: ffffffff8eb3e8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x820 kernel/rcu/tree_exp.h:996
1 lock held by syz.9.16979/19452:
#0: ffff888040ad60e0 (&type->s_umount_key#103){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888040ad60e0 (&type->s_umount_key#103){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
3 locks held by syz-executor/20155:
#0: ffff8880857ecd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:480 [inline]
#0: ffff8880857ecd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2677
#1: ffff8880857ec078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x60d/0x1260 net/bluetooth/hci_sync.c:5185
#2: ffff88805a6d3338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x71/0x690 net/bluetooth/l2cap_core.c:1761
1 lock held by syz.4.17711/21754:
#0: ffffffff8fec3a48 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8fec3a48 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517
1 lock held by syz.7.17713/21751:
#0: ffffffff8eb3e8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
#0: ffffffff8eb3e8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc6-syzkaller-00007-g0b46b049d6ec #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__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:236 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:399
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 21751 Comm: syz.7.17713 Not tainted 6.14.0-rc6-syzkaller-00007-g0b46b049d6ec #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:lockdep_hardirqs_on_prepare+0x128/0x780 kernel/locking/lockdep.c:4389
Code: 00 fc ff df 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 80 3c 13 00 74 12 4c 89 f7 e8 52 08 8a 00 48 ba 00 00 00 00 00 fc ff df <f6> 44 24 41 02 0f 85 8a 03 00 00 48 c7 c0 80 b9 61 9a 48 c1 e8 03
RSP: 0018:ffffc9001d6975c0 EFLAGS: 00000046
RAX: 0000000000000004 RBX: 1ffff92003ad2ec0 RCX: ffffffff9a61b903
RDX: dffffc0000000000 RSI: ffffffff8c802c00 RDI: ffffffff8c802bc0
RBP: ffffc9001d697668 R08: ffffffff903bce77 R09: 1ffffffff20779ce
R10: dffffc0000000000 R11: fffffbfff20779cf R12: dffffc0000000000
R13: 1ffff92003ad2ed0 R14: ffffc9001d697600 R15: 1ffff92003ad2ebc
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e71bff8 CR3: 000000000e938000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
trace_hardirqs_on+0x28/0x40 kernel/trace/trace_preemptirq.c:78
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
_raw_spin_unlock_irqrestore+0x8f/0x140 kernel/locking/spinlock.c:194
__debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
debug_check_no_obj_freed+0x561/0x580 lib/debugobjects.c:1129
remove_vm_area+0x1d3/0x300 mm/vmalloc.c:3241
vfree+0x7f/0x360 mm/vmalloc.c:3364
kcov_put kernel/kcov.c:439 [inline]
kcov_close+0x28/0x50 kernel/kcov.c:535
__fput+0x3e9/0x9f0 fs/file_table.c:464
task_work_run+0x24f/0x310 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0xa2a/0x28e0 kernel/exit.c:938
do_group_exit+0x207/0x2c0 kernel/exit.c:1087
get_signal+0x168c/0x1720 kernel/signal.c:3036
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:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a79d8d169
Code: Unable to access opcode bytes at 0x7f1a79d8d13f.
RSP: 002b:00007ffdae3c1508 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000010f243 RCX: 00007f1a79d8d169
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f1a79fa7ba0 R08: 0000000000000001 R09: 00000003ae3c17ff
R10: 00007f1a79c00000 R11: 0000000000000246 R12: 00007f1a79fa5fac
R13: 00007f1a79fa5fa0 R14: ffffffffffffffff R15: 00007ffdae3c1620
</TASK>