INFO: task syz.0.1836:11038 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1836 state:D stack:23056 pid:11038 ppid:4286 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
perf_pending_task_sync kernel/events/core.c:5031 [inline]
_free_event+0x176/0x1050 kernel/events/core.c:5037
put_event kernel/events/core.c:5162 [inline]
perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5287
perf_release+0x37/0x40 kernel/events/core.c:5297
__fput+0x20a/0x8b0 fs/file_table.c:320
task_work_run+0x1d0/0x260 kernel/task_work.c:203
get_signal+0x118d/0x1340 kernel/signal.c:2649
arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcbc919ce59
RSP: 002b:00007fcbca13efd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007fcbc9415fa0 RCX: 00007fcbc919ce59
RDX: 00002000000001c0 RSI: 0000200000000110 RDI: 0000000040000000
RBP: 00007fcbc9232e6f R08: 0000200000000240 R09: 0000200000000240
R10: 0000200000000200 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fcbc9416038 R14: 00007fcbc9415fa0 R15: 00007fffb36dd8d8
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/27:
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
4 locks held by kworker/u4:2/29:
#0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc90000a5fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#2: ffffffff8dd3c650 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:594
#3: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x18/0x1c0 drivers/net/wireguard/device.c:420
3 locks held by kworker/u4:4/56:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc90001577d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#2: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
2 locks held by getty/4030:
#0: ffff88814dab8098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
3 locks held by kworker/1:3/4320:
#0: ffff88802f62f538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc900044a7d00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#2: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x15/0x30 net/ipv6/addrconf.c:4672
3 locks held by kworker/u4:12/7291:
2 locks held by kworker/1:0/12611:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc9000c91fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
2 locks held by syz.2.2534/13549:
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3495
#1: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#1: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962
1 lock held by syz.5.2536/13563:
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3495
1 lock held by syz.1.2538/13570:
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x80d/0xfb0 net/core/rtnetlink.c:6155
1 lock held by syz.5.2539/13577:
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3f3/0x1ed0 drivers/net/tun.c:3107
1 lock held by syz.5.2539/13578:
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3f3/0x1ed0 drivers/net/tun.c:3107
1 lock held by syz.4.2541/13584:
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x80d/0xfb0 net/core/rtnetlink.c:6155
3 locks held by syz.4.2541/13585:
#0: ffffffff8dda97b0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860
#1: ffff888078d22698 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}, at: __netlink_dump_start+0x11e/0x6f0 net/netlink/af_netlink.c:2310
#2: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_prepare_wdev_dump+0x3d1/0x690 net/wireless/nl80211.c:1011
1 lock held by syz.3.2542/13589:
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3f3/0x1ed0 drivers/net/tun.c:3107
1 lock held by syz.3.2542/13590:
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3495
1 lock held by syz.3.2542/13591:
#0: ffffffff8dd494e8 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x54d/0xe80 net/core/dev_ioctl.c:571
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf0e/0xf50 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7291 Comm: kworker/u4:12 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:__kasan_check_read+0x2/0x10 mm/kasan/shadow.c:31
Code: 41 5d 41 5e 41 5f 5d c3 48 c7 c7 ea ce 60 8c eb 0a 48 c7 c7 01 76 45 8c 48 89 de e8 98 5b 4c 08 31 ed eb d7 00 00 cc cc 89 f6 <48> 8b 0c 24 31 d2 e9 c3 ec ff ff 0f 1f 00 89 f6 48 8b 0c 24 ba 01
RSP: 0018:ffffc900045af8f8 EFLAGS: 00000093
RAX: 0000000000000000 RBX: ffff8880b8e00000 RCX: 76cc68c598ae8400
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b8e35808
RBP: ffffc900045af9d8 R08: ffffffff8e200f6f R09: 1ffffffff1c401ed
R10: dffffc0000000000 R11: fffffbfff1c401ee R12: dffffc0000000000
R13: 0000000000000000 R14: ffff8880b8e35800 R15: 0000000000000002
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fefea892e9c CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
instrument_atomic_read include/linux/instrumented.h:72 [inline]
atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline]
ct_dynticks include/linux/context_tracking_state.h:61 [inline]
ct_nmi_enter+0xfa/0x170 kernel/context_tracking.c:299
ct_irq_enter_irqson+0xaf/0x170 kernel/context_tracking.c:407
trace_irq_disable_rcuidle+0x9f/0x140 include/trace/events/preemptirq.h:36
___slab_alloc+0x1e3/0x1240 mm/slub.c:3055
__slab_alloc mm/slub.c:3240 [inline]
slab_alloc_node mm/slub.c:3325 [inline]
kmem_cache_alloc_node+0x134/0x310 mm/slub.c:3404
__alloc_skb+0xf9/0x7d0 net/core/skbuff.c:505
alloc_skb include/linux/skbuff.h:1303 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x24f/0xa80 drivers/net/netdevsim/dev.c:851
process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295