INFO: task syz.0.1657:13382 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1657 state:D stack:27200 pid:13382 tgid:13381 ppid:5630 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
nfsd_nl_expkey_set_reqs_doit+0xfe/0xaf0 fs/nfsd/export.c:561
genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775
__sock_sendmsg net/socket.c:790 [inline]
____sys_sendmsg+0x54e/0x850 net/socket.c:2684
___sys_sendmsg+0x2a5/0x360 net/socket.c:2738
__sys_sendmsg net/socket.c:2770 [inline]
__do_sys_sendmsg net/socket.c:2775 [inline]
__se_sys_sendmsg net/socket.c:2773 [inline]
__x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2773
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0343b9de99
RSP: 002b:00007f0344a74028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f0343e25fa0 RCX: 00007f0343b9de99
RDX: 0000000020040080 RSI: 0000200000000100 RDI: 0000000000000005
RBP: 00007f0343c33eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0343e26038 R14: 00007f0343e25fa0 R15: 00007ffd4aadf1f8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5376:
#0: ffff8880356610a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5623:
3 locks held by kworker/0:14/8266:
#0: ffff88801b027140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#0: ffff88801b027140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#1: ffffc90005eafc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline]
#1: ffffc90005eafc40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405
#2: ffff888025086250 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1fd/0x3b0 drivers/net/netdevsim/fib.c:1490
3 locks held by kworker/u8:36/9287:
4 locks held by kworker/u8:37/9288:
2 locks held by syz.3.1345/12037:
#0: ffffffff9009cba8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ee8e620 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x135/0x1750 fs/nfsd/nfsctl.c:1964
2 locks held by syz.0.1657/13382:
#0: ffffffff9009cba8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ee8e620 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_expkey_set_reqs_doit+0xfe/0xaf0 fs/nfsd/export.c:561
1 lock held by syz.6.2319/16294:
#0: ffff88807770aa80 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
#0: ffff88807770aa80 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release net/socket.c:709 [inline]
#0: ffff88807770aa80 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: sock_close+0x82/0x220 net/socket.c:1501
2 locks held by syz.1.2321/16298:
#0: ffff888059a19940 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
#0: ffff888059a19940 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release net/socket.c:709 [inline]
#0: ffff888059a19940 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: sock_close+0x82/0x220 net/socket.c:1501
#1: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
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+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 9287 Comm: kworker/u8:36 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: krds_cp_wq#1/5 rds_connect_worker
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3802 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3821 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3876 [inline]
RIP: 0010:__lock_acquire+0xac4/0x2cf0 kernel/locking/lockdep.c:5237
Code: 90 48 bb eb 83 b5 80 46 86 c8 61 48 0f af dd 48 c1 eb 2d 48 8b 04 dd 40 e5 2f 94 48 85 c0 74 1c 48 83 c0 f8 74 16 48 8b 48 18 <48> 39 e9 0f 84 bb 01 00 00 48 8b 40 08 48 85 c0 75 e4 e8 25 d5 ff
RSP: 0018:ffffc9000426f110 EFLAGS: 00000097
RAX: ffffffff948f3250 RBX: 0000000000058227 RCX: 5632626688a35aeb
RDX: 0000000088a25428 RSI: 00000000b6edec50 RDI: ffff88807c7c9f00
RBP: 5632626688a35aeb R08: ffffffff84de1370 R09: 0000000000080000
R10: 0000000000000000 R11: ffffffff9aa306c0 R12: ffff88807c7cab68
R13: ffff88807c7cab68 R14: ffff88807c7c9f00 R15: 0000000000000005
FS: 0000000000000000(0000) GS:ffff88812505e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f27483ed2f8 CR3: 00000000256f2000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
debug_object_assert_init+0xb0/0x380 lib/debugobjects.c:1070
debug_hrtimer_assert_init kernel/time/hrtimer.c:495 [inline]
hrtimer_start_range_ns+0x3d/0x3e0 kernel/time/hrtimer.c:1499
hrtimer_start include/linux/hrtimer.h:223 [inline]
hrtick_cond_restart kernel/sched/core.c:939 [inline]
hrtick_schedule_exit kernel/sched/core.c:1001 [inline]
finish_lock_switch kernel/sched/core.c:5240 [inline]
finish_task_switch+0x3c4/0xc60 kernel/sched/core.c:5359
context_switch kernel/sched/core.c:5513 [inline]
__schedule+0x17e1/0x56c0 kernel/sched/core.c:7234
preempt_schedule_notrace+0x57/0x90 kernel/sched/core.c:7506
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x7f/0xb0 kernel/rcu/tree.c:753
trace_lock_acquire include/trace/events/lock.h:23 [inline]
lock_acquire+0x5f/0x350 kernel/locking/lockdep.c:5831
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock include/linux/rcupdate.h:840 [inline]
__inet6_bind+0x4b7/0xf30 net/ipv6/af_inet6.c:336
kernel_bind+0x13e/0x1c0 net/socket.c:3646
rds_tcp_conn_path_connect+0x53b/0x920 net/rds/tcp_connect.c:175
rds_connect_worker+0x1d8/0x290 net/rds/threads.c:176
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245