INFO: task syz.0.2042:12021 blocked for more than 145 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.2042 state:D stack:28920 pid:12021 tgid:12012 ppid:5615 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5402 [inline]
__schedule+0x16f9/0x5500 kernel/sched/core.c:7204
__schedule_loop kernel/sched/core.c:7283 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7579
rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1666
__rt_mutex_slowlock kernel/locking/rtmutex.c:1743 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1783 [inline]
rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1823
__rt_mutex_lock kernel/locking/rtmutex.c:1838 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:560 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:578
epoll_mutex_lock fs/eventpoll.c:2512 [inline]
ep_ctl_lock fs/eventpoll.c:2559 [inline]
do_epoll_ctl_file+0x9d1/0xed0 fs/eventpoll.c:2636
do_epoll_ctl fs/eventpoll.c:2698 [inline]
__do_sys_epoll_ctl fs/eventpoll.c:2715 [inline]
__se_sys_epoll_ctl+0x14e/0x210 fs/eventpoll.c:2706
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: 0033:0x7f23b91ece59
RSP: 002b:00007f23b73fc028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9
RAX: ffffffffffffffda RBX: 00007f23b9466180 RCX: 00007f23b91ece59
RDX: 0000000000000004 RSI: 0000000000000001 RDI: 0000000000000007
RBP: 00007f23b9282d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f23b9466218 R14: 00007f23b9466180 R15: 00007ffc9fcad718
Showing all locks held in the system:
1 lock held by khungtaskd/39:
#0: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
2 locks held by getty/5370:
#0: ffff88803689d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
3 locks held by syz.4.1192/9276:
#0: ffffffff8e3589b8 (epnested_mutex){+.+.}-{4:4}, at: epoll_mutex_lock fs/eventpoll.c:2512 [inline]
#0: ffffffff8e3589b8 (epnested_mutex){+.+.}-{4:4}, at: ep_ctl_lock fs/eventpoll.c:2559 [inline]
#0: ffffffff8e3589b8 (epnested_mutex){+.+.}-{4:4}, at: do_epoll_ctl_file+0x9d1/0xed0 fs/eventpoll.c:2636
#1: ffff88805d90c858 (&ep->mtx){+.+.}-{4:4}, at: epoll_mutex_lock fs/eventpoll.c:2512 [inline]
#1: ffff88805d90c858 (&ep->mtx){+.+.}-{4:4}, at: ep_ctl_lock fs/eventpoll.c:2573 [inline]
#1: ffff88805d90c858 (&ep->mtx){+.+.}-{4:4}, at: do_epoll_ctl_file+0xc69/0xed0 fs/eventpoll.c:2636
#2: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#2: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#2: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: reverse_path_check fs/eventpoll.c:1691 [inline]
#2: ffffffff8e1cac60 (rcu_read_lock){....}-{1:3}, at: ep_insert+0xbbb/0x1820 fs/eventpoll.c:1881
3 locks held by kworker/1:8/9621:
#0: ffff88813fe17938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3293
#1: ffffc900087b7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3294
#2: ffff88804bec3280 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490
1 lock held by syz.0.2042/12021:
#0: ffffffff8e3589b8 (epnested_mutex){+.+.}-{4:4}, at: epoll_mutex_lock fs/eventpoll.c:2512 [inline]
#0: ffffffff8e3589b8 (epnested_mutex){+.+.}-{4:4}, at: ep_ctl_lock fs/eventpoll.c:2559 [inline]
#0: ffffffff8e3589b8 (epnested_mutex){+.+.}-{4:4}, at: do_epoll_ctl_file+0x9d1/0xed0 fs/eventpoll.c:2636
3 locks held by kworker/u8:24/12052:
#0: ffff88802b738938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3293
#1: ffffc900045d7c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3294
#2: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x124/0x1680 net/ipv6/addrconf.c:4221
2 locks held by kworker/u8:36/12514:
#0: ffff88813fe54138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3293
#1: ffffc90003f57c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3294
2 locks held by syz-executor/13081:
#0: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f5ac9f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4150
#1: ffff888034da18b8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_open+0x227/0x420 drivers/net/wireguard/device.c:50
1 lock held by syz.6.2460/13481:
#0: ffffffff8e3589b8 (epnested_mutex){+.+.}-{4:4}, at: epoll_mutex_lock fs/eventpoll.c:2512 [inline]
#0: ffffffff8e3589b8 (epnested_mutex){+.+.}-{4:4}, at: ep_ctl_lock fs/eventpoll.c:2559 [inline]
#0: ffffffff8e3589b8 (epnested_mutex){+.+.}-{4:4}, at: do_epoll_ctl_file+0x9d1/0xed0 fs/eventpoll.c:2636
1 lock held by dhcpcd/13501:
#0: ffff88804edd4358 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1713 [inline]
#0: ffff88804edd4358 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe70 net/packet/af_packet.c:3204
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
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+0xfd3/0x1030 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: 9276 Comm: syz.4.1192 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x40 kernel/rcu/update.c:319
Code: 48 8d 3d 53 9e 77 04 48 c7 c6 79 22 75 8d 67 48 0f b9 3a 90 eb ca cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 31 c0 83 3d d3 62 74 04 00 74 1d 83 3d ea 74 74 04 00
RSP: 0018:ffffc900079cfb18 EFLAGS: 00000286
RAX: 0000000000000000 RBX: ffffc900079cfd70 RCX: 0000000000080000
RDX: ffffc900069b1000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc900079cfcd0 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc900079cfd70 R11: fffff52000f39fb1 R12: 0000000000000000
R13: ffffffff825693cb R14: ffff88803497a6e0 R15: 0000000000000001
FS: 00007f0408cfe6c0(0000) GS:ffff888125d7e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f53fbd9f5a0 CR3: 000000003b5d2000 CR4: 00000000003526f0
Call Trace:
rcu_read_unlock include/linux/rcupdate.h:867 [inline]
reverse_path_check fs/eventpoll.c:1693 [inline]
ep_insert+0xc74/0x1820 fs/eventpoll.c:1881
do_epoll_ctl_file+0x8bb/0xed0 fs/eventpoll.c:2651
do_epoll_ctl fs/eventpoll.c:2698 [inline]
__do_sys_epoll_ctl fs/eventpoll.c:2715 [inline]
__se_sys_epoll_ctl+0x14e/0x210 fs/eventpoll.c:2706
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: 0033:0x7f040aaace59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0408cfe028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9
RAX: ffffffffffffffda RBX: 00007f040ad25fa0 RCX: 00007f040aaace59
RDX: 0000000000000007 RSI: 0000000000000001 RDI: 0000000000000003
RBP: 00007f040ab42d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000580 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f040ad26038 R14: 00007f040ad25fa0 R15: 00007ffe91c9f188