INFO: task syz.4.115:6659 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.115 state:D stack:24648 pid:6659 tgid:6658 ppid:5804 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x14de/0x5210 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
io_schedule+0x80/0xe0 kernel/sched/core.c:7831
folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1323
folio_lock include/linux/pagemap.h:1170 [inline]
release_metapage+0x103/0xab0 fs/jfs/jfs_metapage.c:870
discard_metapage fs/jfs/jfs_metapage.h:88 [inline]
__get_metapage+0x9a3/0xde0 fs/jfs/jfs_metapage.c:753
dtSplitPage+0x791/0x37c0 fs/jfs/jfs_dtree.c:1471
dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
dtInsert+0x10a4/0x5f10 fs/jfs/jfs_dtree.c:871
jfs_create+0x75b/0xb10 fs/jfs/namei.c:138
lookup_open fs/namei.c:4483 [inline]
open_last_lookups fs/namei.c:4583 [inline]
path_openat+0x13b4/0x38a0 fs/namei.c:4827
do_file_open+0x23e/0x4a0 fs/namei.c:4859
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fac8d8dc629
RSP: 002b:00007fac8bb2e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fac8db55fa0 RCX: 00007fac8d8dc629
RDX: 0000000000000042 RSI: 00002000000002c0 RDI: ffffffffffffff9c
RBP: 00007fac8d972b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fac8db56038 R14: 00007fac8db55fa0 R15: 00007fffda685be8
INFO: task syz.4.115:6682 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.115 state:D stack:25912 pid:6682 tgid:6658 ppid:5804 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x14de/0x5210 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7285
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
__rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1466 [inline]
down_read+0x132/0x200 kernel/locking/rwsem.c:1539
inode_lock_shared include/linux/fs.h:1043 [inline]
lookup_slow+0x46/0x70 fs/namei.c:1932
walk_component fs/namei.c:2279 [inline]
link_path_walk+0xd1e/0x18d0 fs/namei.c:2647
path_parentat fs/namei.c:2851 [inline]
__filename_parentat+0x27f/0x6f0 fs/namei.c:2875
filename_parentat fs/namei.c:2893 [inline]
filename_create+0xd9/0x370 fs/namei.c:4903
filename_mkdirat+0xd2/0x520 fs/namei.c:5259
__do_sys_mkdirat fs/namei.c:5287 [inline]
__se_sys_mkdirat+0x35/0x150 fs/namei.c:5284
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fac8d8dc629
RSP: 002b:00007fac8bb0d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fac8db56090 RCX: 00007fac8d8dc629
RDX: 000000000000001b RSI: 0000200000000380 RDI: ffffffffffffff9c
RBP: 00007fac8d972b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fac8db56128 R14: 00007fac8db56090 R15: 00007fffda685be8
INFO: task syz.4.115:6683 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.115 state:D stack:25272 pid:6683 tgid:6658 ppid:5804 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x14de/0x5210 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7285
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
inode_lock_nested include/linux/fs.h:1073 [inline]
__start_dirop fs/namei.c:2923 [inline]
start_dirop fs/namei.c:2934 [inline]
filename_unlinkat+0x2ad/0x610 fs/namei.c:5521
__do_sys_unlink fs/namei.c:5575 [inline]
__se_sys_unlink+0x2e/0x140 fs/namei.c:5572
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fac8d8dc629
RSP: 002b:00007fac8baec028 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007fac8db56180 RCX: 00007fac8d8dc629
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000440
RBP: 00007fac8d972b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fac8db56218 R14: 00007fac8db56180 R15: 00007fffda685be8
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:4/68:
#0: ffff88813fe74138 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88813fe74138 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3358
#1: ffffc9000153fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc9000153fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3358
#2: ffffffff8ef4e138 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
7 locks held by kworker/u8:5/1008:
4 locks held by kworker/u8:6/1151:
#0: ffff88801ee9f138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88801ee9f138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3358
#1: ffffc90004517c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc90004517c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3358
#2: ffff888030ff00d0 (&type->s_umount_key#64){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff88806063ed28 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
2 locks held by getty/5549:
#0: ffff88802826e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e762e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
4 locks held by syz-executor/5791:
4 locks held by syz.4.115/6659:
#0: ffff888030ff0480 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff88806063f0f8 (&type->i_mutex_dir_key#13){++++}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#1: ffff88806063f0f8 (&type->i_mutex_dir_key#13){++++}-{4:4}, at: open_last_lookups fs/namei.c:4580 [inline]
#1: ffff88806063f0f8 (&type->i_mutex_dir_key#13){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4827
#2: ffff88806063ed28 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_create+0x22e/0xb10 fs/jfs/namei.c:101
#3: ffff888040461f28 (&jfs_ip->commit_mutex/1){+.+.}-{4:4}, at: jfs_create+0x249/0xb10 fs/jfs/namei.c:102
1 lock held by syz.4.115/6682:
#0: ffff88806063f0f8 (&type->i_mutex_dir_key#13){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline]
#0: ffff88806063f0f8 (&type->i_mutex_dir_key#13){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1932
2 locks held by syz.4.115/6683:
#0: ffff888030ff0480 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff88806063f0f8 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff88806063f0f8 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline]
#1: ffff88806063f0f8 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline]
#1: ffff88806063f0f8 (&type->i_mutex_dir_key#13/1){+.+.}-{4:4}, at: filename_unlinkat+0x2ad/0x610 fs/namei.c:5521
4 locks held by udevd/6784:
1 lock held by udevd/6937:
5 locks held by syz-executor/7464:
3 locks held by syz.7.433/8725:
1 lock held by syz-executor/8726:
#0: ffffffff8ef4e138 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8ef4e138 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978
1 lock held by syz.2.436/8730:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xf90/0xfe0 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 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: 1008 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: netns cleanup_net
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+0x197b/0x2cf0 kernel/locking/lockdep.c:5237
Code: 13 25 ff 0f 00 00 39 05 ff 4e 91 11 73 06 89 05 f7 4e 91 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 f0 a6 a9
RSP: 0018:ffffc90004426b78 EFLAGS: 00000006
RAX: ffffffff95b98528 RBX: 00000000000003cd RCX: 000000000000002d
RDX: ffffffff95b4a9c8 RSI: ffff88802636e6a8 RDI: 00000000000003cd
RBP: 01d3499eaa797569 R08: ffffc90004426b40 R09: 0000000000000020
R10: dffffc0000000000 R11: ffffffff819f7a40 R12: ffffffff95b72118
R13: ffffffff92d20850 R14: ffff88802636da00 R15: 000000000000002c
FS: 0000000000000000(0000) GS:ffff888126595000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f76529f4000 CR3: 000000003cf52000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
do_write_seqcount_begin_nested include/linux/seqlock.h:478 [inline]
do_write_seqcount_begin include/linux/seqlock.h:504 [inline]
psi_write_begin+0xab/0x160 kernel/sched/psi.c:183
psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
psi_sched_switch kernel/sched/stats.h:225 [inline]
__schedule+0x25dd/0x5210 kernel/sched/core.c:6901
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234
irqentry_exit+0x599/0x620 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:-1 [inline]
RIP: 0010:udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:249 [inline]
RIP: 0010:__udp_tunnel_nic_device_sync+0x964/0x1580 net/ipv4/udp_tunnel_nic.c:292
Code: e0 48 c1 e8 03 48 89 84 24 88 00 00 00 48 c7 44 24 08 00 00 00 00 4c 89 64 24 68 eb 20 e8 34 a8 23 f8 49 89 df 4c 8b 64 24 68 <48> 8b 84 24 90 00 00 00 42 c6 44 38 04 f8 48 ff 44 24 08 48 83 7c
RSP: 0018:ffffc90004427120 EFLAGS: 00000293
RAX: ffffffff899f6d4c RBX: dffffc0000000000 RCX: ffff88802636da00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004427280 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 00000000fffffffe R12: ffff8880294320e8
R13: ffff8880294320d4 R14: ffff88805c0f77c0 R15: dffffc0000000000
udp_tunnel_nic_flush+0x2cc/0x670 net/ipv4/udp_tunnel_nic.c:694
udp_tunnel_nic_unregister net/ipv4/udp_tunnel_nic.c:901 [inline]
udp_tunnel_nic_netdevice_event+0xfb2/0x17d0 net/ipv4/udp_tunnel_nic.c:942
notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2281 [inline]
call_netdevice_notifiers net/core/dev.c:2295 [inline]
unregister_netdevice_many_notify+0x186a/0x2360 net/core/dev.c:12396
unregister_netdevice_many net/core/dev.c:12459 [inline]
unregister_netdevice_queue+0x31f/0x360 net/core/dev.c:12273
unregister_netdevice include/linux/netdevice.h:3405 [inline]
nsim_destroy+0x1e5/0x680 drivers/net/netdevsim/netdev.c:1180
__nsim_dev_port_del+0x14d/0x1b0 drivers/net/netdevsim/dev.c:1528
nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1540 [inline]
nsim_dev_reload_destroy+0x288/0x490 drivers/net/netdevsim/dev.c:1764
nsim_dev_reload_down+0x8a/0xc0 drivers/net/netdevsim/dev.c:1038
devlink_reload+0x1d1/0x8f0 net/devlink/dev.c:461
devlink_pernet_pre_exit+0x1e6/0x3f0 net/devlink/core.c:509
ops_pre_exit_list net/core/net_namespace.c:161 [inline]
ops_undo_list+0x187/0x940 net/core/net_namespace.c:234
cleanup_net+0x4e5/0x7b0 net/core/net_namespace.c:696
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3358
worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245