INFO: task syz.1.350:8651 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.350 state:D stack:26840 pid:8651 tgid:8650 ppid:8033 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0x147b/0x4f50 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7245
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
__super_lock fs/super.c:59 [inline]
super_lock+0x2d6/0x3d0 fs/super.c:121
__iterate_supers+0x126/0x290 fs/super.c:923
ksys_sync+0xa0/0x170 fs/sync.c:102
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f150162acb9
RSP: 002b:00007f14ff886028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f15018a5fa0 RCX: 00007f150162acb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f15018a5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f15018a6038 R14: 00007f15018a5fa0 R15: 00007ffd2899c5a8
Showing all locks held in the system:
3 locks held by kworker/0:0/9:
#0: ffff88813fe15138 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813fe15138 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc900000e7bc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc900000e7bc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
3 locks held by rcuc/1/28:
1 lock held by kauditd/37:
#0: ffffffff8da1c798 (kauditd_wait.lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#0: ffffffff8da1c798 (kauditd_wait.lock){+.+.}-{3:3}, at: finish_wait+0xbe/0x1e0 kernel/sched/wait.c:394
1 lock held by khungtaskd/38:
#0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:3/57:
#0: ffff88801aa94938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88801aa94938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc9000123fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000123fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffffffff8ed29560 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0 net/core/net_namespace.c:670
#3: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
#3: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x2a4/0x940 net/core/net_namespace.c:248
3 locks held by kworker/u8:6/811:
#0: ffff88813fe29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813fe29938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc900043a7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc900043a7bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
2 locks held by getty/5558:
#0: ffff888027b010a0 (&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+0x462/0x13c0 drivers/tty/n_tty.c:2211
4 locks held by syz-executor/8093:
1 lock held by syz.1.350/8651:
#0: ffff888026f8a0d0 (&type->s_umount_key#89){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff888026f8a0d0 (&type->s_umount_key#89){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:121
2 locks held by syz-executor/8805:
2 locks held by udevd/8933:
#0: ffff888035fa0480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
#1: ffff88802f6434d8 (&type->i_mutex_dir_key#5){++++}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
#1: ffff88802f6434d8 (&type->i_mutex_dir_key#5){++++}-{4:4}, at: open_last_lookups fs/namei.c:4546 [inline]
#1: ffff88802f6434d8 (&type->i_mutex_dir_key#5){++++}-{4:4}, at: path_openat+0xb65/0x3e70 fs/namei.c:4793
3 locks held by udevd/9124:
#0: ffff888035fa0480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
#1: ffff8880348734d8 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline]
#1: ffff8880348734d8 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2873 [inline]
#1: ffff8880348734d8 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2884 [inline]
#1: ffff8880348734d8 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4888
#2: ffffffff8da1c798 (kauditd_wait.lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#2: ffffffff8da1c798 (kauditd_wait.lock){+.+.}-{3:3}, at: __wake_up_common_lock+0x2f/0x1e0 kernel/sched/wait.c:124
2 locks held by udevd/9237:
2 locks held by syz-executor/9395:
#0: ffffffff8e497508 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e497508 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e497508 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8ed37ef8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071
3 locks held by syz.3.431/9533:
5 locks held by syz.5.433/9545:
1 lock held by dhcpcd-run-hook/9547:
#0: ffffffff8da1c798 (kauditd_wait.lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#0: ffffffff8da1c798 (kauditd_wait.lock){+.+.}-{3:3}, at: __wake_up_common_lock+0x2f/0x1e0 kernel/sched/wait.c:124
=============================================
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 01/13/2026
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+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 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 01/13/2026
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+0xfb/0x340 kernel/locking/lockdep.c:6281
Code: c6 fc 0f 84 e1 00 00 00 41 c1 ee 08 4a 8d 1c 75 90 e3 0a 92 49 81 fe 00 00 50 00 73 2f 0f b7 03 25 ff 1f 00 00 49 39 c7 74 33 <49> ff c6 41 8b 45 00 89 c1 c1 e9 08 c1 e8 02 83 e0 3f 01 c8 48 83
RSP: 0018:ffffc90000087bc8 EFLAGS: 00000002
RAX: 0000000000000869 RBX: ffffffff920fde96 RCX: 0000000000094e97
RDX: ffffffff9305e3d8 RSI: ffffffff9305e3d8 RDI: ffffffff92b35d28
RBP: ffffffff9309e830 R08: ffffffff81ab56a8 R09: ffffffff8d9c7780
R10: dffffc0000000000 R11: fffffbfff1e4f3ef R12: 0000000000013de9
R13: ffffffff931c7e30 R14: 0000000000027d83 R15: 0000000000000ad9
FS: 0000000000000000(0000) GS:ffff8881267fc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f441615b080 CR3: 000000002fb6c000 CR4: 00000000003526f0
Call Trace:
__lockdep_free_key_range kernel/locking/lockdep.c:6407 [inline]
lockdep_unregister_key+0x1c3/0x350 kernel/locking/lockdep.c:6609
wq_unregister_lockdep kernel/workqueue.c:4852 [inline]
pwq_release_workfn+0x6d2/0x870 kernel/workqueue.c:5148
kthread_worker_fn+0x4ee/0xb00 kernel/kthread.c:1005
kthread+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246