INFO: task syz.4.329:8189 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.329 state:D stack:24008 pid:8189 tgid:8188 ppid:5816 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7307
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
inode_lock_nested include/linux/fs.h:1025 [inline]
filename_create+0x1f8/0x3c0 fs/namei.c:4226
do_mkdirat+0xa0/0x590 fs/namei.c:4478
__do_sys_mkdirat fs/namei.c:4503 [inline]
__se_sys_mkdirat fs/namei.c:4501 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4501
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff2a6a3de17
RSP: 002b:00007ff2a4ca5e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007ff2a4ca5ef0 RCX: 00007ff2a6a3de17
RDX: 00000000000001ff RSI: 0000200000000100 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000200000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000100
R13: 00007ff2a4ca5eb0 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz.4.329:8200 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.329 state:D stack:24280 pid:8200 tgid:8188 ppid:5816 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
io_schedule+0x81/0xe0 kernel/sched/core.c:7871
folio_wait_bit_common+0x6b5/0xb90 mm/filemap.c:1330
folio_lock include/linux/pagemap.h:1141 [inline]
release_metapage+0x103/0xab0 fs/jfs/jfs_metapage.c:870
discard_metapage fs/jfs/jfs_metapage.h:88 [inline]
__get_metapage+0x9a0/0xde0 fs/jfs/jfs_metapage.c:753
dtSplitPage+0x7f8/0x3b20 fs/jfs/jfs_dtree.c:1471
dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
dtInsert+0x109b/0x5f40 fs/jfs/jfs_dtree.c:871
jfs_create+0x6c8/0xa80 fs/jfs/namei.c:137
lookup_open fs/namei.c:3796 [inline]
open_last_lookups fs/namei.c:3895 [inline]
path_openat+0x1500/0x3840 fs/namei.c:4131
do_filp_open+0x1fa/0x410 fs/namei.c:4161
do_sys_openat2+0x121/0x1c0 fs/open.c:1437
do_sys_open fs/open.c:1452 [inline]
__do_sys_open fs/open.c:1460 [inline]
__se_sys_open fs/open.c:1456 [inline]
__x64_sys_open+0x11e/0x150 fs/open.c:1456
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff2a6a3f6c9
RSP: 002b:00007ff2a4c85038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007ff2a6c96090 RCX: 00007ff2a6a3f6c9
RDX: 389b0d52417bb201 RSI: 0000000000064842 RDI: 00002000000005c0
RBP: 00007ff2a6ac1f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff2a6c96128 R14: 00007ff2a6c96090 R15: 00007ffedc73c418
Showing all locks held in the system:
1 lock held by khungtaskd/39:
#0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5aa840 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
5 locks held by kworker/u8:7/3081:
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff888019ad4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000ce97ba0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000ce97ba0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffffffff8e8564e0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x820 net/core/net_namespace.c:669
#3: ffff88805abc97b8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_destruct+0x116/0x2f0 drivers/net/wireguard/device.c:249
#4: ffffffff8d5b01f0 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3820
3 locks held by kworker/u8:11/3583:
#0: ffff88801f6a9138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88801f6a9138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000d897ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000d897ba0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffff88806141a0d0 (&type->s_umount_key#68){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562
3 locks held by kworker/u8:14/3683:
#0: ffff88802fe23938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88802fe23938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000daa7ba0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000daa7ba0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x119/0x15a0 net/ipv6/addrconf.c:4194
2 locks held by dhcpcd/5468:
#0: ffffffff8e847858 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5f1/0x790 net/socket.c:1337
#1: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:579
2 locks held by getty/5568:
#0: ffff88823bf700a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/5813:
2 locks held by syz.4.329/8189:
#0: ffff88806141a480 (sb_writers#28){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508
#1: ffff88805acf5d78 (&type->i_mutex_dir_key#18/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1025 [inline]
#1: ffff88805acf5d78 (&type->i_mutex_dir_key#18/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4226
4 locks held by syz.4.329/8200:
#0: ffff88806141a480 (sb_writers#28){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508
#1: ffff88805acf5d78 (&type->i_mutex_dir_key#21){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline]
#1: ffff88805acf5d78 (&type->i_mutex_dir_key#21){++++}-{4:4}, at: open_last_lookups fs/namei.c:3892 [inline]
#1: ffff88805acf5d78 (&type->i_mutex_dir_key#21){++++}-{4:4}, at: path_openat+0x8e6/0x3840 fs/namei.c:4131
#2: ffff88805acf59a8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_create+0x1f5/0xa80 fs/jfs/namei.c:100
#3: ffff88805acf0ba8 (&jfs_ip->commit_mutex/1){+.+.}-{4:4}, at: jfs_create+0x210/0xa80 fs/jfs/namei.c:101
1 lock held by syz-executor/9352:
#0: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x5b7/0xd20 net/ipv6/addrconf.c:5027
2 locks held by syz-executor/9583:
#0: ffffffff8dfed420 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8dfed420 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8dfed420 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8e9/0x1c80 net/core/rtnetlink.c:4064
2 locks held by syz-executor/9684:
#0: ffffffff8e8564e0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576
#1: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock_killable include/linux/rtnetlink.h:145 [inline]
#1: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: register_netdev+0x18/0x60 net/core/dev.c:11407
2 locks held by syz-executor/9759:
#0: ffffffff8e8564e0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x337/0x4e0 net/core/net_namespace.c:576
#1: ffffffff8e8633f8 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x80/0x210 net/ipv4/nexthop.c:3971
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
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+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 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: 3 Comm: pool_workqueue_ Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:remove_class_from_lock_chain kernel/locking/lockdep.c:6197 [inline]
RIP: 0010:remove_class_from_lock_chains kernel/locking/lockdep.c:6236 [inline]
RIP: 0010:zap_class+0xbe/0x360 kernel/locking/lockdep.c:6281
Code: 10 49 ff c4 49 81 fc 00 00 08 00 0f 84 a5 01 00 00 4e 8b 2c e5 40 33 66 92 4d 85 ed 0f 94 c0 49 83 c5 f8 0f 94 c1 08 c1 75 d7 <45> 8b 7d 00 41 f6 c7 fc 0f 84 e2 00 00 00 41 c1 ef 08 4e 8d 34 7d
RSP: 0018:ffffc90000087ba0 EFLAGS: 00000046
RAX: 0000000000011700 RBX: 00000000000010b4 RCX: 0000000000011700
RDX: ffffffff92a63358 RSI: ffffffff92a63358 RDI: ffffffff92583fc0
RBP: ffffffff92aa37b0 R08: 0000000000000000 R09: ffffffff81a913d8
R10: dffffc0000000000 R11: fffffbfff1dac76f R12: 000000000003df2e
R13: ffffffff92bc5490 R14: ffffffff91ad61bc R15: 0000000000011756
FS: 0000000000000000(0000) GS:ffff888126ef7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8ae02eff90 CR3: 0000000035614000 CR4: 00000000003526f0
Call Trace:
__lockdep_free_key_range kernel/locking/lockdep.c:6407 [inline]
lockdep_unregister_key+0x1a6/0x310 kernel/locking/lockdep.c:6609
wq_unregister_lockdep kernel/workqueue.c:4848 [inline]
pwq_release_workfn+0x6d2/0x870 kernel/workqueue.c:5144
kthread_worker_fn+0x507/0xb60 kernel/kthread.c:1010
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245