INFO: task syz.2.1696:13617 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.2.1696 state:D stack:28232 pid:13617 tgid:13615 ppid:5826 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7004
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
nfsd_nl_threads_set_doit+0x718/0xc60 fs/nfsd/nfsctl.c:1597
genl_family_rcv_msg_doit+0x214/0x300 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0x560/0x800 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x159/0x420 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+0x5aa/0x870 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa54/0xc30 net/socket.c:2592
___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
__sys_sendmsg+0x170/0x220 net/socket.c:2678
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feb4459c799
RSP: 002b:00007feb45371028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007feb44816090 RCX: 00007feb4459c799
RDX: 000000000000c000 RSI: 0000200000000480 RDI: 0000000000000004
RBP: 00007feb44632bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007feb44816128 R14: 00007feb44816090 R15: 00007ffc959d4558
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e7e9220 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7e9220 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7e9220 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
3 locks held by kworker/0:3/5818:
#0: ffff88813fe63548 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
#1: ffffc90003b07d08 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
#2: ffff88807d545240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1b8/0x63b0 drivers/net/netdevsim/fib.c:1490
2 locks held by syz-executor/5823:
#0: ffff88805beee0e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88805beee0e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88805beee0e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff88805beee0e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz-executor/5824:
#0: ffff88802ce680e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88802ce680e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88802ce680e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff88802ce680e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz-executor/5825:
#0: ffff8880387920e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880387920e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff8880387920e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff8880387920e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
3 locks held by kworker/1:4/5894:
#0: ffff88813fe62148 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
#1: ffffc90003f77d08 ((crda_timeout).work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
#2: ffffffff90612f28 (rtnl_mutex){+.+.}-{4:4}, at: crda_timeout_work+0x16/0x70 net/wireless/reg.c:540
2 locks held by getty/10498:
#0: ffff888029b000a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900049dd2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
2 locks held by syz.2.1696/13616:
#0: ffffffff906bf0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b20 fs/nfsd/nfsctl.c:1893
2 locks held by syz.2.1696/13617:
#0: ffffffff906bf0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x718/0xc60 fs/nfsd/nfsctl.c:1597
2 locks held by syz-executor/13870:
#0: ffff888052fae0e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888052fae0e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888052fae0e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff888052fae0e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz-executor/14264:
#0: ffff888090e660e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888090e660e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888090e660e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff888090e660e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz-executor/14306:
#0: ffff88807dae00e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88807dae00e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88807dae00e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff88807dae00e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz-executor/14430:
#0: ffff888033a880e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888033a880e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888033a880e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff888033a880e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz-executor/14548:
#0: ffff88807d6300e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88807d6300e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88807d6300e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff88807d6300e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz-executor/15107:
#0: ffff88806005e0e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88806005e0e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88806005e0e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff88806005e0e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz.9.2012/15147:
#0: ffffffff906bf0b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xd5/0x1b20 fs/nfsd/nfsctl.c:1893
2 locks held by syz-executor/15163:
#0: ffff88802577a0e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88802577a0e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88802577a0e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff88802577a0e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
2 locks held by syz-executor/15373:
#0: ffff888023b2c0e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888023b2c0e0 (&type->s_umount_key#55){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff888023b2c0e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super fs/super.c:508 [inline]
#0: ffff888023b2c0e0 (&type->s_umount_key#55){++++}-{4:4}, at: deactivate_super+0xdf/0x110 fs/super.c:505
#1: ffffffff8ec586e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:575
1 lock held by syz-executor/15653:
#0: ffffffff8e7f4e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
3 locks held by syz.4.2129/15706:
#0: ffffffff905fa5f0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577
#1: ffffffff90612f28 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
#1: ffffffff90612f28 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
#2: ffffffff8e7f4e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
2 locks held by syz.4.2129/15707:
#0: ffffffff905fa5f0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577
#1: ffffffff8e7f4d00 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6d0 kernel/rcu/tree.c:3828
2 locks held by syz.2.2132/15720:
#0: ffffffff905fa5f0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:577
#1: ffffffff90612f28 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x21e/0x780 net/ipv4/ip_tunnel.c:1146
4 locks held by syz.7.2134/15726:
#0: ffff88802a3ccec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0xb0 net/bluetooth/hci_core.c:500
#1: ffff88802a3cc0c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x35c/0x1240 net/bluetooth/hci_sync.c:5346
#2: ffffffff908aaf28 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline]
#2: ffffffff908aaf28 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x280 net/bluetooth/hci_conn.c:2644
#3: ffff8880603b72f8 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x80/0x770 net/bluetooth/l2cap_core.c:1755
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 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 lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 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+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xd25/0x1050 kernel/hung_task.c:515
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 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: 11753 Comm: kworker/u8:21 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:__kfree_rcu_sheaf+0xf2/0x720 mm/slub.c:5913
Code: e8 43 00 25 09 41 89 c6 83 f8 07 0f 87 28 05 00 00 4a 03 1c f5 e0 88 12 8e 4c 8b 73 48 4d 85 f6 0f 84 a5 01 00 00 41 8b 46 18 <8d> 50 01 41 89 56 18 4d 89 64 c6 20 3b 55 2c 0f 83 00 02 00 00 48
RSP: 0018:ffffc90007617078 EFLAGS: 00000286
RAX: 000000000000001a RBX: ffff8880b853f6a8 RCX: 0000000000000005
RDX: 0000000000000000 RSI: ffffffff8c1af020 RDI: ffffffff8c1af060
RBP: ffff88813fe3c280 R08: 00000000a505816c R09: 000000000000002c
R10: 0000000000000200 R11: 0000000000000000 R12: ffff888060f4eb80
R13: ffff888029d98000 R14: ffff88807e9f0800 R15: ffffc900076172e0
FS: 0000000000000000(0000) GS:ffff88812444e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f51d09e9e80 CR3: 000000000e598000 CR4: 00000000003526f0
Call Trace:
kfree_rcu_sheaf mm/slab_common.c:1608 [inline]
kvfree_call_rcu+0x1b6/0x4f0 mm/slab_common.c:1957
cfg80211_update_known_bss+0x4f3/0x1300 net/wireless/scan.c:1943
__cfg80211_bss_update+0x1b6/0x23e0 net/wireless/scan.c:1988
cfg80211_inform_single_bss_data+0x770/0x1e20 net/wireless/scan.c:2368
cfg80211_inform_bss_data+0x237/0x3a00 net/wireless/scan.c:3226
cfg80211_inform_bss_frame_data+0x247/0x790 net/wireless/scan.c:3317
ieee80211_bss_info_update+0x310/0xab0 net/mac80211/scan.c:230
ieee80211_rx_bss_info net/mac80211/ibss.c:1094 [inline]
ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1575 [inline]
ieee80211_ibss_rx_queued_mgmt+0x1919/0x2f80 net/mac80211/ibss.c:1602
ieee80211_iface_process_skb net/mac80211/iface.c:1748 [inline]
ieee80211_iface_work+0xbff/0x13d0 net/mac80211/iface.c:1802
cfg80211_wiphy_work+0x446/0x5c0 net/wireless/core.c:440
process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275
process_scheduled_works kernel/workqueue.c:3358 [inline]
worker_thread+0x5da/0xe40 kernel/workqueue.c:3439
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245