INFO: task syz.6.8586:31613 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.8586 state:D stack:27144 pid:31613 tgid:31612 ppid:17766 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6908
__schedule_loop kernel/sched/core.c:6990 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7005
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7062
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
nfsd_nl_version_get_doit+0x17c/0xc40 fs/nfsd/nfsctl.c:1818
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+0x80f/0x9b0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0x972/0x9f0 net/socket.c:2592
___sys_sendmsg+0x2a5/0x360 net/socket.c:2646
__sys_sendmsg net/socket.c:2678 [inline]
__do_sys_sendmsg net/socket.c:2683 [inline]
__se_sys_sendmsg net/socket.c:2681 [inline]
__x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681
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: 0033:0x7f190719c799
RSP: 002b:00007f1907faf028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1907415fa0 RCX: 00007f190719c799
RDX: 0000000000000000 RSI: 00002000000032c0 RDI: 0000000000000003
RBP: 00007f1907232c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1907416038 R14: 00007f1907415fa0 R15: 00007ffcddbc9568
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e75e420 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e75e420 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e75e420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5572:
#0: ffff8880374390a0 (&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+0x45c/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by syz.0.5845/19801:
#0: ffffffff8fc3ab30 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ea858a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x141/0x1670 fs/nfsd/nfsctl.c:1893
2 locks held by syz.6.8586/31613:
#0: ffffffff8fc3ab30 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ea858a8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_get_doit+0x17c/0xc40 fs/nfsd/nfsctl.c:1818
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026
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: 20110 Comm: kworker/u8:10 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/27/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:process_one_work kernel/workqueue.c:3275 [inline]
RIP: 0010:process_scheduled_works+0xaea/0x1830 kernel/workqueue.c:3358
Code: 00 fc ff df 0f 84 7a 07 00 00 e8 61 e8 36 00 eb 0f e8 5a e8 36 00 49 be 00 00 00 00 00 fc ff df 48 8b 44 24 78 42 80 3c 30 00 <74> 08 4c 89 ef e8 fc 22 a1 00 4d 8b 5d 00 48 8b 3c 24 2e e8 5e 08
RSP: 0018:ffffc90002fd7b00 EFLAGS: 00000246
RAX: 1ffff11006941d63 RBX: ffffffff818eb4a5 RCX: ffff88807cd11e80
RDX: 0000000000000000 RSI: ffffffff8c27b3e0 RDI: ffffffff8c27b3a0
RBP: ffffc90002fd7ce8 R08: ffffffff90118bb7 R09: 1ffffffff2023176
R10: dffffc0000000000 R11: fffffbfff2023177 R12: ffff888029694000
R13: ffff888034a0eb18 R14: dffffc0000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125463000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555591eeea28 CR3: 000000007ad71000 CR4: 0000000000350ef0
Call Trace:
worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
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