INFO: task syz.4.2068:13924 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.4.2068 state:D stack:28232 pid:13924 tgid:13923 ppid:5820 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0xfee/0x6120 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7008
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
nfsd_nl_threads_set_doit+0x6c1/0xc00 fs/nfsd/nfsctl.c:1607
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+0x9e1/0xb70 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: 0033:0x7fb7b939c819
RSP: 002b:00007fb7ba1ab028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fb7b9615fa0 RCX: 00007fb7b939c819
RDX: 0000000004000080 RSI: 0000200000000100 RDI: 0000000000000003
RBP: 00007fb7b9432c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb7b9616038 R14: 00007fb7b9615fa0 R15: 00007fff8ec0dcf8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7e7920 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:6/510:
#0: ffff888033c12948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc90003e67d08 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffffffff90613ba8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff90613ba8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4738
1 lock held by syslogd/5162:
2 locks held by getty/5565:
#0: ffff8880397220a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
6 locks held by kworker/1:3/5862:
#0: ffff888020af0d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc90003c1fd08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffff88802aaa91e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#2: ffff88802aaa91e0 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
#3: ffff8880340e61e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#3: ffff8880340e61e0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068
#4: ffff88803c4e21a8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#4: ffff88803c4e21a8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1068
#5: ffffffff90613ba8 (rtnl_mutex){+.+.}-{4:4}, at: wpan_phy_register+0x27/0x160 net/ieee802154/core.c:145
3 locks held by kworker/0:6/5910:
#0: ffff888020af0d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc90003dcfd08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffff88802ab231e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#2: ffff88802ab231e0 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
3 locks held by kworker/u8:12/12101:
#0: ffff88813fea4148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc90004cb7d08 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffffffff90613ba8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:313
4 locks held by udevd/13138:
#0: ffff888083daf540 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
#1: ffff888078c82088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
#2: ffff88807e651e18 (kn->active#29){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff88807e651e18 (kn->active#29){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
#3: ffff88802b52f1e0 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:954 [inline]
#3: ffff88802b52f1e0 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
7 locks held by kworker/0:1/13853:
#0: ffff888020af0d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc9001bfcfd08 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffff88802b0221e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#2: ffff88802b0221e0 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
#3: ffff88802b52f1e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#3: ffff88802b52f1e0 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336
#4: ffff888055c0b1a8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#4: ffff888055c0b1a8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1166 [inline]
#4: ffff888055c0b1a8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1364
#5: ffffffff8fe1d108 (input_mutex){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#5: ffffffff8fe1d108 (input_mutex){+.+.}-{4:4}, at: __input_unregister_device+0x184/0x4d0 drivers/input/input.c:2187
#6: ffffffff8e7f3478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
2 locks held by syz.0.2066/13909:
#0: ffffffff906bfed0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec59d88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x6c1/0xc00 fs/nfsd/nfsctl.c:1607
2 locks held by syz.4.2068/13924:
#0: ffffffff906bfed0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8ec59d88 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x6c1/0xc00 fs/nfsd/nfsctl.c:1607
4 locks held by syz.3.2456/15644:
#0: ffffffff90da0248 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline]
#0: ffffffff90da0248 (&ops->srcu#2){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline]
#0: ffffffff90da0248 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x113/0x2c0 net/core/rtnetlink.c:574
#1: ffffffff90613ba8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff90613ba8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff90613ba8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8bb/0x2380 net/core/rtnetlink.c:4093
#2: ffff8880790d98d8 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_flowtable_event+0x14d/0x1d0 net/netfilter/nf_tables_api.c:9738
#3: ffffffff8e7f3478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by syz.6.2457/15645:
#0: ffffffff90613ba8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff90613ba8 (rtnl_mutex){+.+.}-{4:4}, at: dev_ioctl+0x331/0x10e0 net/core/dev_ioctl.c:813
=============================================
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 03/18/2026
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:436
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: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: d8 81 02 c3 cc cc cc cc 0f 1f 00 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 a3 91 1a 00 fb f4 fc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df0 EFLAGS: 00000246
RAX: 00000000067a5b69 RBX: ffff88801e69a4c0 RCX: ffffffff8b90fc75
RDX: 0000000000000000 RSI: ffffffff8de79dfe RDI: ffffffff8c1b1a20
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10170a679d
R10: ffff8880b8533ceb R11: 0000000000000000 R12: 0000000000000001
R13: ffffed1003cd3498 R14: 0000000000000001 R15: ffffffff90d9c710
FS: 0000000000000000(0000) GS:ffff88812443c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f15b6fe92f8 CR3: 0000000027d84000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: 0000000000000fff DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:73 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x464/0x590 kernel/sched/idle.c:352
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:451
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148