INFO: task kworker/u10:8:17574 blocked for more than 143 seconds.
Tainted: G U L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u10:8 state:D stack:23512 pid:17574 tgid:17574 ppid:2 task_flags:0x4208160 flags:0x00080000
Workqueue: netns cleanup_net
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_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2e7/0x4c0 kernel/sched/completion.c:121
__debugfs_file_removed fs/debugfs/inode.c:751 [inline]
remove_one+0x312/0x420 fs/debugfs/inode.c:758
__simple_recursive_removal+0x148/0x5c0 fs/libfs.c:625
debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:781
nsim_dev_health_exit+0x3b/0xe0 drivers/net/netdevsim/health.c:227
nsim_dev_reload_destroy+0x144/0x4a0 drivers/net/netdevsim/dev.c:1767
nsim_dev_reload_down+0x66/0xd0 drivers/net/netdevsim/dev.c:1038
devlink_reload+0x173/0x790 net/devlink/dev.c:461
devlink_pernet_pre_exit+0x222/0x330 net/devlink/core.c:507
ops_pre_exit_list net/core/net_namespace.c:161 [inline]
ops_undo_list+0x187/0xab0 net/core/net_namespace.c:234
cleanup_net+0x499/0x920 net/core/net_namespace.c:704
process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
process_scheduled_works kernel/workqueue.c:3359 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
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
INFO: task syz.7.4854:30831 blocked for more than 144 seconds.
Tainted: G U L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.4854 state:D stack:27288 pid:30831 tgid:30824 ppid:30436 task_flags:0x400040 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
devlink_health_report+0x681/0xb50 net/devlink/health.c:680
nsim_dev_health_break_write+0x166/0x210 drivers/net/netdevsim/health.c:162
full_proxy_write+0x135/0x1a0 fs/debugfs/file.c:388
vfs_write+0x2aa/0x1070 fs/read_write.c:686
ksys_write+0x12a/0x250 fs/read_write.c:740
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: 0033:0x7f8def79c799
RSP: 002b:00007f8df06b7028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f8defa16090 RCX: 00007f8def79c799
RDX: 00000000000001e1 RSI: 0000200000000080 RDI: 0000000000000005
RBP: 00007f8def832c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8defa16128 R14: 00007f8defa16090 R15: 00007fffcd3e88b8
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by kworker/1:3/1214:
#0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc90004e7fd08 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
2 locks held by getty/5590:
#0: ffff888037b620a0 (&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
3 locks held by kworker/0:7/5949:
#0: ffff88813fe63148 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc900043b7d08 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffffffff8e7f32b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
6 locks held by kworker/u10:8/17574:
#0: ffff88801c6b6948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1310/0x19a0 kernel/workqueue.c:3251
#1: ffffc9000eb37d08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x988/0x19a0 kernel/workqueue.c:3252
#2: ffffffff905fd910 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:675
#3: ffff888026d69130 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:949 [inline]
#3: ffff888026d69130 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
#3: ffff888026d69130 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x185/0x330 net/devlink/core.c:504
#4: ffff88807e4d9250 (&devlink->lock_key#13){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:274 [inline]
#4: ffff88807e4d9250 (&devlink->lock_key#13){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
#4: ffff88807e4d9250 (&devlink->lock_key#13){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x18f/0x330 net/devlink/core.c:504
#5: ffff88805dd19f78 (&sb->s_type->i_mutex_key#10/2){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#5: ffff88805dd19f78 (&sb->s_type->i_mutex_key#10/2){+.+.}-{4:4}, at: __simple_recursive_removal+0xe0/0x5c0 fs/libfs.c:621
8 locks held by kworker/u10:15/21130:
5 locks held by kworker/u10:17/21132:
#0: ffff8880b843b360 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:655 [inline]
#0: ffff8880b843b360 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:639
#1: ffff8880b8424648 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:225 [inline]
#1: ffff8880b8424648 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2c11/0x6120 kernel/sched/core.c:6905
#2: ffff8880b8426358 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x124/0x1d0 kernel/time/timer.c:1004
#3: ffffffff9b3dd750 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x144/0x490 lib/debugobjects.c:835
#4: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#4: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#4: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
#4: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x1ea0 arch/x86/kernel/unwind_orc.c:495
5 locks held by kworker/u10:21/21138:
#0: ffff8880b843b360 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:655 [inline]
#0: ffff8880b843b360 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x88/0x140 kernel/sched/core.c:639
#1: ffff8880b8424648 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:225 [inline]
#1: ffff8880b8424648 (psi_seq){-.-.}-{0:0}, at: __schedule+0x2c11/0x6120 kernel/sched/core.c:6905
#2: ffff888079253268 (&rtn->rds_tcp_accept_lock){+.+.}-{4:4}, at: rds_tcp_accept_one+0xb1/0xe70 net/rds/tcp_listen.c:172
#3: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#3: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#3: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
#3: ffffffff8e7e7760 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x1ea0 arch/x86/kernel/unwind_orc.c:495
#4: ffff888062581c60 (k-slock-AF_INET6){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:347 [inline]
#4: ffff888062581c60 (k-slock-AF_INET6){+.-.}-{3:3}, at: release_sock+0x21/0x220 net/core/sock.c:3793
1 lock held by syz.6.4659/29634:
#0: ffffffff90616168 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90616168 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
1 lock held by syz-executor/30473:
#0: ffffffff90616168 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90616168 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
3 locks held by syz.7.4854/30831:
#0: ffff8880645b0b78 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1261
#1: ffff8880202c6420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:740
#2: ffff88807e4d9250 (&devlink->lock_key#13){+.+.}-{4:4}, at: devlink_health_report+0x681/0xb50 net/devlink/health.c:680
1 lock held by syz-executor/31065:
#0: ffffffff90616168 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff90616168 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
5 locks held by syz.5.5095/32141:
#0: ffff8880309430b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1261
#1: ffff8880364f0420 (sb_writers#7){.+.+}-{0:0}, at: do_writev+0x13e/0x340 fs/read_write.c:1105
#2: ffff88802b7f5c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343
#3: ffff88801f7ec5a8 (kn->active#118){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#3: ffff88801f7ec5a8 (kn->active#118){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344
#4: ffff88807e4d9250 (&devlink->lock_key#13){+.+.}-{4:4}, at: nsim_drv_port_add+0x59/0x1a0 drivers/net/netdevsim/dev.c:1814
2 locks held by syz-executor/32362:
#0: ffff88804f7f0ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0xb0 net/bluetooth/hci_core.c:500
#1: ffff88804f7f00c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x35c/0x1240 net/bluetooth/hci_sync.c:5346
2 locks held by syz.9.5326/828:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G U L syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [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: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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 22166 Comm: kworker/u10:32 Tainted: G U L syzkaller #0 PREEMPT(full)
Tainted: [U]=USER, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: krdsd rds_tcp_accept_worker
RIP: 0010:__lock_acquire+0x131/0x2630 kernel/locking/lockdep.c:5172
Code: 0f b7 46 20 25 ff 1f 00 00 44 39 e8 75 09 4d 85 e4 0f 85 99 05 00 00 48 8b 04 24 44 89 ea 66 81 e2 ff 1f 48 01 c3 0f b7 43 20 <4c> 89 53 10 4c 89 63 18 66 25 00 e0 09 d0 31 d2 66 89 43 20 48 8b
RSP: 0018:ffffc90004427398 EFLAGS: 00000096
RAX: 0000000000000007 RBX: ffff888034d26750 RCX: 0000000000000003
RDX: 0000000000000007 RSI: ffff888034d26728 RDI: ffffffff8e7e7760
RBP: ffff888034d25b80 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff8e7e7760 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000007 R14: 0000000000000002 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124343000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f00a3547e20 CR3: 000000000e598000 CR4: 00000000003526f0
Call Trace:
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x1cf/0x380 kernel/locking/lockdep.c:5825
rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
rcu_read_lock include/linux/rcupdate.h:850 [inline]
class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0xd1/0x1ea0 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556
__call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3131
destroy_inode+0x134/0x1c0 fs/inode.c:402
evict+0x599/0xad0 fs/inode.c:870
iput_final fs/inode.c:1966 [inline]
iput.part.0+0x605/0xf50 fs/inode.c:2015
iput+0x35/0x40 fs/inode.c:1981
__sock_release+0x1fc/0x260 net/socket.c:674
sock_release net/socket.c:690 [inline]
kernel_accept+0x2a3/0x350 net/socket.c:3601
rds_tcp_accept_one+0x3f4/0xe70 net/rds/tcp_listen.c:177
rds_tcp_accept_worker+0x41/0x60 net/rds/tcp.c:530
process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
process_scheduled_works kernel/workqueue.c:3359 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
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