INFO: task syz.0.9633:10591 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.9633 state:D stack:26728 pid:10591 tgid:10588 ppid:9219 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
nfsd_nl_version_set_doit+0xcd/0x7a0 fs/nfsd/nfsctl.c:1753
genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:722 [inline]
__sock_sendmsg net/socket.c:737 [inline]
____sys_sendmsg+0x972/0x9f0 net/socket.c:2633
___sys_sendmsg+0x2a5/0x360 net/socket.c:2687
__sys_sendmsg net/socket.c:2719 [inline]
__do_sys_sendmsg net/socket.c:2724 [inline]
__se_sys_sendmsg net/socket.c:2722 [inline]
__x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2722
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2159d9c819
RSP: 002b:00007f215abba028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f215a015fa0 RCX: 00007f2159d9c819
RDX: 0000000004008090 RSI: 0000200000000140 RDI: 0000000000000004
RBP: 00007f2159e32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f215a016038 R14: 00007f215a015fa0 R15: 00007ffcd18ebe88
Showing all locks held in the system:
3 locks held by kworker/0:0/9:
#0: ffff88813fe13148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff88813fe13148 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc900000e7c40 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc900000e7c40 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffffffff8e764780 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by khungtaskd/30:
#0: ffffffff8e75e5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e75e5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e75e5a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by klogd/5184:
#0: ffff8880b863ae60 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647
2 locks held by getty/5579:
#0: ffff8880375e20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
4 locks held by kworker/u8:19/6180:
#0: ffff8880b863ae60 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647
#1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
#2: ffff8880b8626118 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x8ee/0xf30 kernel/time/timer.c:1117
#3: ffffffff9a583408 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x83/0x580 lib/debugobjects.c:835
2 locks held by syz.4.8696/6684:
#0: ffffffff8fc3a810 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ea86b48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x1670 fs/nfsd/nfsctl.c:1903
2 locks held by syz.0.9633/10591:
#0: ffffffff8fc3a810 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ea86b48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xcd/0x7a0 fs/nfsd/nfsctl.c:1753
1 lock held by syz.6.11411/17559:
#0: ffff88808480f068 (&pipe->mutex){+.+.}-{4:4}, at: pipe_release+0x48/0x330 fs/pipe.c:729
1 lock held by syz.6.11411/17561:
#0: ffff88808480f068 (&pipe->mutex){+.+.}-{4:4}, at: splice_file_to_pipe+0x40/0x6b0 fs/splice.c:1287
1 lock held by syz.6.11411/17577:
#0: ffff88808480f068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15b/0x1480 fs/pipe.c:458
2 locks held by syz.5.11424/17611:
#0: ffffffff8fbcb6c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fbcb6c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3438
#1: ffffffff8e7648b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e7648b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
3 locks held by syz.1.11427/17629:
#0: ffff888055bc7ac8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff888055bc7ac8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: __sock_release net/socket.c:656 [inline]
#0: ffff888055bc7ac8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1449
#1: ffff888025bca260 (sk_lock-AF_CAN){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#1: ffff888025bca260 (sk_lock-AF_CAN){+.+.}-{0:0}, at: bcm_release+0x1cd/0x940 net/can/bcm.c:1611
#2: ffffffff8e7648b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8e7648b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [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:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:mark_held_locks kernel/locking/lockdep.c:4313 [inline]
RIP: 0010:__trace_hardirqs_on_caller kernel/locking/lockdep.c:4351 [inline]
RIP: 0010:lockdep_hardirqs_on_prepare+0x127/0x260 kernel/locking/lockdep.c:4410
Code: ba 03 00 00 00 83 da 00 48 89 df 4c 89 e6 e8 80 62 00 00 85 c0 75 bc eb 79 48 c7 c7 90 c7 62 8e 4c 89 fe e8 fb 75 4a 03 eb c2 <85> c0 7e 64 83 bb 38 0b 00 00 00 74 5b 45 31 ff eb 13 49 ff c7 48
RSP: 0018:ffffc90000007b38 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffffffff8e494ec0 RCX: ffffffff93cc6720
RDX: 0000000000000002 RSI: ffffffff8e495a18 RDI: ffffffff8e494ec0
RBP: ffffffff9a54e990 R08: ffffffff9011d4b7 R09: 1ffffffff2023a96
R10: dffffc0000000000 R11: fffffbfff2023a97 R12: ffffffff8e495a40
R13: ffff888044209ee0 R14: ffffffff8e495a18 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125447000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa0a4de92f8 CR3: 000000007517e000 CR4: 00000000003526f0
Call Trace:
trace_hardirqs_on+0x28/0x40 kernel/trace/trace_preemptirq.c:78
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline]
_raw_spin_unlock_irqrestore+0x30/0x80 kernel/locking/spinlock.c:194
debug_object_assert_init+0x209/0x370 lib/debugobjects.c:1026
debug_timer_assert_init kernel/time/timer.c:803 [inline]
debug_assert_init kernel/time/timer.c:848 [inline]
__mod_timer+0x4a/0xf30 kernel/time/timer.c:1025
call_timer_fn+0x192/0x640 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2373 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385
run_timer_base kernel/time/timer.c:2394 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404
handle_softirqs+0x22a/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: fe 6a 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d e3 82 15 00 fb f4 fc e9 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8e407dc0 EFLAGS: 00000246
RAX: 00000000003f752d RBX: ffffffff819a8d1a RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8df2facf RDI: ffffffff8c27d480
RBP: ffffffff8e407eb0 R08: ffff8880b863399b R09: 1ffff110170c6733
R10: dffffc0000000000 R11: ffffed10170c6734 R12: 0000000000000000
R13: 1ffffffff1c929d8 R14: 0000000000000000 R15: 1ffffffff1c929d8
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x36a/0x5f0 kernel/sched/idle.c:352
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451
rest_init+0x2de/0x300 init/main.c:760
start_kernel+0x385/0x3d0 init/main.c:1210
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147