INFO: task syz.4.5357:26305 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.4.5357 state:D stack:28120 pid:26305 tgid:26301 ppid:13652 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5352 [inline]
__schedule+0x165c/0x5560 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7047 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7062
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7119
__mutex_lock_common kernel/locking/mutex.c:710 [inline]
__mutex_lock+0x856/0x1420 kernel/locking/mutex.c:794
nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:576
nfsd_umount+0x41/0x60 fs/nfsd/nfsctl.c:1364
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:269 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe02d59c799
RSP: 002b:00007fe02e407028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: fffffffffffffffe RBX: 00007fe02d816090 RCX: 00007fe02d59c799
RDX: 0000200000000780 RSI: 00002000000000c0 RDI: 0000000000000000
RBP: 00007fe02d632c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe02d816128 R14: 00007fe02d816090 R15: 00007ffee90888b8
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e75d7e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e75d7e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e75d7e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5595:
#0: ffff8880386220a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
2 locks held by syz.3.4177/22088:
#0: ffffffff8fc43a88 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ea87c00 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2b5/0x9a0 fs/nfsd/nfsctl.c:1607
2 locks held by syz.4.5357/26305:
#0: ffff888057b3a0d8 (&type->s_umount_key#114){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888057b3a0d8 (&type->s_umount_key#114){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888057b3a0d8 (&type->s_umount_key#114){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffffffff8ea87c00 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:576
1 lock held by syz.9.5652/27598:
#0: ffff888057b3a0d8 (&type->s_umount_key#114){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888057b3a0d8 (&type->s_umount_key#114){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
1 lock held by syz.2.5704/27850:
#0: ffff888057b3a0d8 (&type->s_umount_key#114){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888057b3a0d8 (&type->s_umount_key#114){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
3 locks held by syz-executor/28023:
#0: ffffffff8fbd5580 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8fbd5580 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8fbd5580 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071
#1: ffff888063b3cd98 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2790 [inline]
#1: ffff888063b3cd98 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: netdev_lock_ops include/net/netdev_lock.h:42 [inline]
#1: ffff888063b3cd98 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: do_setlink+0x3d2/0x4590 net/core/rtnetlink.c:3068
#2: ffffffff8e763a28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e763a28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
1 lock held by syz.8.5758/28119:
#0: ffffffff8e7638f8 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
1 lock held by syz.5.5759/28131:
#0: ffffffff8e7638f8 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x580 kernel/rcu/tree.c:3828
3 locks held by dhcpcd-run-hook/28147:
=============================================
NMI backtrace for cpu 0
CPU: 0 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 02/12/2026
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: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+0xfd3/0x1030 kernel/hung_task.c:561
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 28023 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:preempt_latency_start kernel/sched/core.c:5800 [inline]
RIP: 0010:preempt_count_add+0x74/0x190 kernel/sched/core.c:5826
Code: c1 e8 03 42 0f b6 04 38 84 c0 0f 85 e5 00 00 00 83 3d 6f 30 94 18 00 75 11 65 8b 05 f6 cc 88 11 0f b6 c0 3d f5 00 00 00 73 5d <65> 8b 05 e5 cc 88 11 25 ff ff ff 7f 39 f8 75 42 48 8b 5c 24 18 48
RSP: 0018:ffffc90000a08da0 EFLAGS: 00000093
RAX: 0000000000000002 RBX: ffff8880b8728280 RCX: ffffffff9a28d303
RDX: 0000000000010000 RSI: ffffffff8c287360 RDI: 0000000000000001
RBP: ffffc90003a17d40 R08: ffffffff901237f7 R09: 1ffffffff20246fe
R10: dffffc0000000000 R11: fffffbfff20246ff R12: ffff8880b8728280
R13: 1ffff110170e506a R14: ffff8880b87283a0 R15: dffffc0000000000
FS: 0000555581b34500(0000) GS:ffff888125549000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdb5993bc8 CR3: 000000006b106000 CR4: 00000000003526f0
Call Trace:
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:141 [inline]
_raw_spin_lock_irq+0x21/0x50 kernel/locking/spinlock.c:174
__run_hrtimer kernel/time/hrtimer.c:1934 [inline]
__hrtimer_run_queues+0x46a/0xa20 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x435/0x8e0 kernel/time/hrtimer.c:2112
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline]
RIP: 0010:vprintk_emit+0x45d/0x560 kernel/printk/printk.c:2478
Code: 0f 84 44 ff ff ff e8 32 05 21 00 fb eb 44 e8 2a 05 21 00 e8 75 3c 0b 0a 4d 85 f6 74 94 e8 1b 05 21 00 fb 48 c7 c7 00 fc 74 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 cb 18
RSP: 0018:ffffc9000d3be8e0 EFLAGS: 00000293
RAX: ffffffff81a546f5 RBX: ffffffff81a5456f RCX: ffff888048811e80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e74fc00
RBP: ffffc9000d3be990 R08: ffffffff901237f7 R09: 1ffffffff20246fe
R10: dffffc0000000000 R11: fffffbfff20246ff R12: 0000000000000000
R13: 0000000000000032 R14: 0000000000000200 R15: 1ffff92001a77d20
dev_vprintk_emit+0x355/0x420 drivers/base/core.c:4916
dev_printk_emit+0xee/0x140 drivers/base/core.c:4927
__netdev_printk+0x3e1/0x480 net/core/dev.c:12971
netdev_info+0x11e/0x180 net/core/dev.c:13026
netif_change_name+0x895/0x960 net/core/dev.c:1485
do_setlink+0xb6c/0x4590 net/core/rtnetlink.c:3138
rtnl_changelink net/core/rtnetlink.c:3776 [inline]
__rtnl_newlink net/core/rtnetlink.c:3935 [inline]
rtnl_newlink+0x15a9/0x1be0 net/core/rtnetlink.c:4072
rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6958
netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec+0x112/0x150 net/socket.c:796
__sock_sendmsg net/socket.c:811 [inline]
__sys_sendto+0x3ff/0x590 net/socket.c:2279
__do_sys_sendto net/socket.c:2286 [inline]
__se_sys_sendto net/socket.c:2282 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2282
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: 0033:0x7f3342d5cfce
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007fff93f65418 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000555581b34500 RCX: 00007f3342d5cfce
RDX: 0000000000000030 RSI: 00007f3343b43610 RDI: 0000000000000006
RBP: 0000000000000001 R08: 00007fff93f65494 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 0000000000000000 R14: 00007f3343b43610 R15: 0000000000000000