INFO: task kworker/u8:3:49 blocked for more than 146 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:3 state:D stack:18424 pid:49 tgid:49 ppid:2 task_flags:0x4208160 flags:0x00080000
Workqueue: netns cleanup_net
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1480/0x50a0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6960
rxrpc_destroy_all_calls+0x564/0x660 net/rxrpc/call_object.c:757
rxrpc_exit_net+0x6f/0xc0 net/rxrpc/net_ns.c:112
ops_exit_list net/core/net_namespace.c:199 [inline]
ops_undo_list+0x49a/0x990 net/core/net_namespace.c:252
cleanup_net+0x4de/0x7b0 net/core/net_namespace.c:696
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
INFO: task syz.2.792:8510 blocked for more than 146 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.792 state:D stack:26464 pid:8510 tgid:8507 ppid:5818 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1480/0x50a0 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241
rt_mutex_slowlock_block+0x5ba/0x6d0 kernel/locking/rtmutex.c:1647
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline]
rt_mutex_slowlock+0x2a8/0x6b0 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline]
mutex_lock_nested+0x16a/0x1d0 kernel/locking/rtmutex_api.c:552
sync_bdevs+0x27e/0x470 block/bdev.c:1305
ksys_sync+0xb9/0x150 fs/sync.c:105
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7eff28a1f749
RSP: 002b:00007eff26c86038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007eff28c75fa0 RCX: 00007eff28a1f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007eff28c75fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007eff28c76038 R14: 00007eff28c75fa0 R15: 00007fffcb894168
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d5aecc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5aecc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5aecc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:3/49:
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc90000bb7b80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90000bb7b80 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8e88a860 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x7b0 net/core/net_namespace.c:670
2 locks held by udevd/5177:
2 locks held by getty/5569:
#0: ffff88814dced0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
9 locks held by syz-executor/5796:
1 lock held by udevd/5882:
#0: ffff888024a8a4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:962
1 lock held by udevd/5972:
#0: ffff888024cd54c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:962
1 lock held by udevd/5974:
#0: ffff888024bbe4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:962
3 locks held by kworker/0:10/6133:
1 lock held by udevd/7443:
#0: ffff888024ce54c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:962
1 lock held by syz.2.792/8510:
#0: ffff888024ce54c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470 block/bdev.c:1305
1 lock held by syz-executor/8690:
1 lock held by syz.1.1164/9970:
#0: ffff888024a8a4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:962
3 locks held by kworker/0:16/10060:
2 locks held by syz-executor/10098:
3 locks held by syz-executor/10099:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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:332 [inline]
watchdog+0xf3c/0xf80 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5796 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__bfs kernel/locking/lockdep.c:1815 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x197c/0x2cf0 kernel/locking/lockdep.c:5237
Code: 13 25 ff 0f 00 00 39 05 9e 87 17 11 73 06 89 05 96 87 17 11 48 8b 02 48 89 df 4c 39 e8 0f 84 2c fe ff ff 4c 89 60 30 48 8b 00 <4c> 39 e8 75 f4 48 89 df e9 18 fe ff ff 48 89 fb 48 c7 c7 10 e4 47
RSP: 0018:ffffc90004e47798 EFLAGS: 00000002
RAX: ffffffff9555a2d8 RBX: 0000000000000101 RCX: 0000000000000004
RDX: ffffffff9538f758 RSI: ffff888033860c80 RDI: 0000000000000101
RBP: d7e73522be426141 R08: ffffc90004e47760 R09: 0000000000000020
R10: dffffc0000000000 R11: ffffffff819d54f0 R12: ffffffff9538fc28
R13: ffffffff925676b8 R14: ffff888033860000 R15: 0000000000000003
FS: 000055557c32e500(0000) GS:ffff888126e52000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0a3d7930fa CR3: 00000000337ea000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x117/0x340 kernel/locking/lockdep.c:5868
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
update_cfs_rq_load_avg kernel/sched/fair.c:4544 [inline]
update_load_avg+0x219/0x1870 kernel/sched/fair.c:4703
enqueue_entity kernel/sched/fair.c:5236 [inline]
enqueue_task_fair+0x2cc/0x2780 kernel/sched/fair.c:6929
enqueue_task+0xb3/0x4c0 kernel/sched/core.c:2094
activate_task kernel/sched/core.c:2135 [inline]
ttwu_do_activate+0x1dc/0x860 kernel/sched/core.c:3631
ttwu_queue kernel/sched/core.c:3894 [inline]
try_to_wake_up+0x721/0x12b0 kernel/sched/core.c:4218
signal_wake_up_state+0xb5/0x120 kernel/signal.c:734
signal_wake_up include/linux/sched/signal.h:450 [inline]
complete_signal+0xa23/0xbc0 kernel/signal.c:1023
__send_signal_locked+0xbb3/0xec0 kernel/signal.c:1153
do_send_sig_info kernel/signal.c:1269 [inline]
group_send_sig_info+0x1f4/0x250 kernel/signal.c:1419
kill_pid_info_type+0xf8/0x1f0 kernel/signal.c:1459
kill_pid_info kernel/signal.c:1473 [inline]
kill_proc_info+0xd9/0x180 kernel/signal.c:1480
kill_something_info kernel/signal.c:1577 [inline]
__do_sys_kill kernel/signal.c:3953 [inline]
__se_sys_kill+0xc4/0x450 kernel/signal.c:3947
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0a3f8aba37
Code: 48 83 c4 08 c3 66 0f 1f 44 00 00 48 c7 c2 a8 ff ff ff 64 89 02 b8 ff ff ff ff eb e4 0f 1f 80 00 00 00 00 b8 3e 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffee1b08c98 EFLAGS: 00000206 ORIG_RAX: 000000000000003e
RAX: ffffffffffffffda RBX: 00007ffee1b091e0 RCX: 00007f0a3f8aba37
RDX: 0000000000000003 RSI: 0000000000000009 RDI: 00000000000016aa
RBP: 000055557c347240 R08: 000055557c3474d0 R09: 000055557c3474f8
R10: 538f731c16db219f R11: 0000000000000206 R12: 00007ffee1b08cac
R13: 000055557c349ec8 R14: 000055557c3474d8 R15: 00007ffee1b08d40