INFO: task syz.5.2807:16998 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.2807 state:D stack:25736 pid:16998 tgid:16996 ppid:11514 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
nfsd_nl_version_get_doit+0x16e/0xb60 fs/nfsd/nfsctl.c:1844
genl_family_rcv_msg_doit+0x212/0x300 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:742
____sys_sendmsg+0x505/0x830 net/socket.c:2627
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2681
__sys_sendmsg net/socket.c:2713 [inline]
__do_sys_sendmsg net/socket.c:2718 [inline]
__se_sys_sendmsg net/socket.c:2716 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f083c58eec9
RSP: 002b:00007f083d49d038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f083c7e5fa0 RCX: 00007f083c58eec9
RDX: 0000000000008800 RSI: 00002000000001c0 RDI: 000000000000000a
RBP: 00007f083c611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f083c7e6038 R14: 00007f083c7e5fa0 R15: 00007ffd1cbe3818
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5624:
#0: ffff88803376c0a0 (&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+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz.9.2238/14846:
#0: ffffffff8f5a0710 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e418b48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1919
2 locks held by syz.5.2807/16998:
#0: ffffffff8f5a0710 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e418b48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_get_doit+0x16e/0xb60 fs/nfsd/nfsctl.c:1844
5 locks held by kworker/u8:15/18486:
#0: ffff8880b8739f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636
#1: ffff8880b8724008 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
#2: ffff88808f6e8788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6358 [inline]
#2: ffff88808f6e8788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xc4/0x470 net/wireless/core.c:421
#3: ffffffff99d50300 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
#4: ffffffff99d5d758 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
3 locks held by kworker/u8:18/18490:
#0: ffff88814d039948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88814d039948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000bed7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000bed7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8f53ac08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f53ac08 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4194
3 locks held by kworker/u8:33/18508:
#0: ffff88801a489948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801a489948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc90002eb7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc90002eb7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8f53ac08 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
2 locks held by syz.8.4132/21851:
#0: ffffffff8f5a0710 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e418b48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1919
2 locks held by syz.0.4407/22916:
#0: ffffffff8f5a0710 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8e418b48 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x137/0x1690 fs/nfsd/nfsctl.c:1919
1 lock held by syz.6.4418/22953:
#0: ffffffff8f53ac08 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8f53ac08 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
2 locks held by syz.6.4418/22971:
#0: ffffffff8f52dd50 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566
#1: ffffffff8f53ac08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#1: ffffffff8f53ac08 (rtnl_mutex){+.+.}-{4:4}, at: register_netdevice_notifier_net+0x1a/0xa0 net/core/dev.c:2082
3 locks held by syz.2.4421/22961:
#0: ffff88804f4b2608 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:870 [inline]
#0: ffff88804f4b2608 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
#0: ffff88804f4b2608 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1452
#1: ffff88807e268e58 (sk_lock-AF_QIPCRTR){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1679 [inline]
#1: ffff88807e268e58 (sk_lock-AF_QIPCRTR){+.+.}-{0:0}, at: qrtr_release+0x52/0x2d0 net/qrtr/af_qrtr.c:1213
#2: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#2: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957
2 locks held by syz.7.4423/22964:
#0: ffffffff8f53ac08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f53ac08 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6960
#1: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e13fb78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
=============================================
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 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 53 e8 02 00 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 b3 69 14 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2
RAX: d15f81697d2b9c00 RBX: ffffffff81968528 RCX: d15f81697d2b9c00
RDX: 0000000000000001 RSI: ffffffff8d9b220d RDI: ffffffff8be33f80
RBP: ffffc90000197f20 R08: ffff8880b8732f9b R09: 1ffff110170e65f3
R10: dffffc0000000000 R11: ffffed10170e65f4 R12: ffffffff8fa30930
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003a53b40
FS: 0000000000000000(0000) GS:ffff888125d39000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33e10ff8 CR3: 0000000063178000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x147