INFO: task syz.1.18:4503 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.18 state:D stack:26736 pid:4503 ppid:4405 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6698
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x548/0xae0 kernel/locking/mutex.c:747
subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
do_dentry_open+0x7dd/0x10b0 fs/open.c:882
do_open fs/namei.c:3634 [inline]
path_openat+0x2674/0x2f10 fs/namei.c:3791
do_filp_open+0x1ee/0x420 fs/namei.c:3818
do_sys_openat2+0x14b/0x4f0 fs/open.c:1320
do_sys_open fs/open.c:1336 [inline]
__do_sys_openat fs/open.c:1352 [inline]
__se_sys_openat fs/open.c:1347 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1347
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7faa0b39e0d9
RSP: 002b:00007ffef1370f58 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007faa0b625fa0 RCX: 00007faa0b39e0d9
RDX: 0000000000000001 RSI: 0000200000000100 RDI: ffffffffffffff9c
RBP: 00007faa0b435024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007faa0b625fac R14: 00007faa0b625fa0 R15: 00007faa0b625fa0
</TASK>
INFO: task syz.0.17:4506 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:26736 pid:4506 ppid:4400 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6698
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x548/0xae0 kernel/locking/mutex.c:747
subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
do_dentry_open+0x7dd/0x10b0 fs/open.c:882
do_open fs/namei.c:3634 [inline]
path_openat+0x2674/0x2f10 fs/namei.c:3791
do_filp_open+0x1ee/0x420 fs/namei.c:3818
do_sys_openat2+0x14b/0x4f0 fs/open.c:1320
do_sys_open fs/open.c:1336 [inline]
__do_sys_openat fs/open.c:1352 [inline]
__se_sys_openat fs/open.c:1347 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1347
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3b7bf9e0d9
RSP: 002b:00007ffeb3dde148 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f3b7c225fa0 RCX: 00007f3b7bf9e0d9
RDX: 0000000000000001 RSI: 0000200000000100 RDI: ffffffffffffff9c
RBP: 00007f3b7c035024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3b7c225fac R14: 00007f3b7c225fa0 R15: 00007f3b7c225fa0
</TASK>
INFO: task syz.4.21:4508 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.21 state:D stack:26304 pid:4508 ppid:4412 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6698
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x548/0xae0 kernel/locking/mutex.c:747
subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
do_dentry_open+0x7dd/0x10b0 fs/open.c:882
do_open fs/namei.c:3634 [inline]
path_openat+0x2674/0x2f10 fs/namei.c:3791
do_filp_open+0x1ee/0x420 fs/namei.c:3818
do_sys_openat2+0x14b/0x4f0 fs/open.c:1320
do_sys_open fs/open.c:1336 [inline]
__do_sys_openat fs/open.c:1352 [inline]
__se_sys_openat fs/open.c:1347 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1347
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb9f1b9e0d9
RSP: 002b:00007ffd97d5b358 EFLAGS: 00000246
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fb9f1e25fa0 RCX: 00007fb9f1b9e0d9
RDX: 0000000000000001 RSI: 0000200000000100 RDI: ffffffffffffff9c
RBP: 00007fb9f1c35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb9f1e25fac R14: 00007fb9f1e25fa0 R15: 00007fb9f1e25fa0
</TASK>
INFO: task syz.2.19:4511 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.19 state:D stack:26688 pid:4511 ppid:4410 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5246 [inline]
__schedule+0x107f/0x4030 kernel/sched/core.c:6563
schedule+0xb9/0x180 kernel/sched/core.c:6639
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6698
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x548/0xae0 kernel/locking/mutex.c:747
subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
do_dentry_open+0x7dd/0x10b0 fs/open.c:882
do_open fs/namei.c:3634 [inline]
path_openat+0x2674/0x2f10 fs/namei.c:3791
do_filp_open+0x1ee/0x420 fs/namei.c:3818
do_sys_openat2+0x14b/0x4f0 fs/open.c:1320
do_sys_open fs/open.c:1336 [inline]
__do_sys_openat fs/open.c:1352 [inline]
__se_sys_openat fs/open.c:1347 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1347
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fde8e59e0d9
RSP: 002b:00007ffc8fdc1e08 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fde8e825fa0 RCX: 00007fde8e59e0d9
RDX: 0000000000000001 RSI: 0000200000000100 RDI: ffffffffffffff9c
RBP: 00007fde8e635024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fde8e825fac R14: 00007fde8e825fa0 R15: 00007fde8e825fa0
</TASK>
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527
5 locks held by kworker/u4:2/41:
4 locks held by kworker/u4:4/57:
2 locks held by getty/4031:
#0: ffff88803078d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
3 locks held by kworker/1:4/4344:
#0: ffff88814c732d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc900040a7d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#2: ffffffff8dd5c0a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xc4/0x1500 net/ipv6/addrconf.c:4138
3 locks held by kworker/u4:8/4456:
#0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#1: ffffc90003437d00 (
(linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
#2: ffffffff8dd5c0a8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
5 locks held by syz.3.20/4502:
1 lock held by syz.1.18/4503:
#0:
ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.0.17/4506:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.4.21/4508:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.2.19/4511:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.5.22/4570:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.6.23/4609:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.8.25/4613:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.7.24/4614:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.9.26/4615:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.1.29/4686:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.0.34/4714:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.2.36/4717:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.4.35/4721:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.5.65/4768:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.6.78/4834:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.7.83/4852:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.8.80/4853:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.9.99/4878:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.1.115/4911:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz-executor/4918:
#0: ffffffff8dd5c0a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8dd5c0a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x80d/0xfb0 net/core/rtnetlink.c:6163
8 locks held by syz-executor/4952:
#0: ffff88807f600460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
#1: ffff88804eb39888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1d8/0x520 fs/kernfs/file.c:343
#2: ffff888143771660 (kn->active#59){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888143771660 (kn->active#59){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x520 fs/kernfs/file.c:344
#3: ffffffff8d66a768 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd3/0x370 drivers/net/netdevsim/bus.c:209
#4: ffff88805cd6d0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:885 [inline]
#4: ffff88805cd6d0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1099 [inline]
#4: ffff88805cd6d0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb1/0x7c0 drivers/base/dd.c:1302
#5: ffff88805cd6c2f8 (&devlink->lock_key#17){+.+.}-{3:3}, at: nsim_drv_remove+0x54/0x170 drivers/net/netdevsim/dev.c:1678
#6: ffffffff8dd5c0a8 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x3b/0x150 drivers/net/netdevsim/netdev.c:381
#7: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#7: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962
1 lock held by syz.2.127/4960:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
1 lock held by syz.0.126/4964:
#0: ffffffff8cb82e28 (event_mutex){+.+.}-{3:3}, at: subsystem_open+0x44/0x380 kernel/trace/trace_events.c:1903
6 locks held by syz.3.160/4979:
#0: ffff88807a994460 (sb_writers#11){.+.+}-{0:0}, at: vfs_write+0x270/0x9a0 fs/read_write.c:580
#1: ffff88804b794c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1d8/0x520 fs/kernfs/file.c:343
#2: ffffffff8cb56648 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:442 [inline]
#2: ffffffff8cb56648 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xe5/0x220 kernel/cgroup/cgroup.c:1700
#3: ffffffff8c9ca530 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2476 [inline]
#3: ffffffff8c9ca530 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x186/0x610 kernel/cgroup/cgroup.c:2983
#4: ffffffff8cb56830 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2478 [inline]
#4: ffffffff8cb56830 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x19c/0x610 kernel/cgroup/cgroup.c:2983
#5: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#5: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<TASK>
dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf0e/0xf50 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:radix_tree_descend lib/radix-tree.c:86 [inline]
RIP: 0010:__radix_tree_lookup lib/radix-tree.c:764 [inline]
RIP: 0010:radix_tree_lookup+0xd9/0x280 lib/radix-tree.c:817
Code: bd 62 61 f7 4c 39 eb 0f 87 8b 01 00 00 4d 89 fc 49 83 e4 fc 49 c1 ef 03 41 0f b6 04 2f 84 c0 0f 85 a7 00 00 00 45 0f b6 3c 24 <bf> 40 00 00 00 44 89 fe e8 0a 63 61 f7 41 83 ff 3f 0f 87 a6 00 00
RSP: 0018:ffffc900001b7950 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000004 RCX: ffff8880176e1e00
RDX: 0000000000000100 RSI: 000000000000003f RDI: 0000000000000004
RBP: dffffc0000000000 R08: ffff8880529cf407 R09: 1ffff1100a539e80
R10: dffffc0000000000 R11: ffffed100a539e81 R12: ffff888017800000
R13: 000000000000003f R14: ffffffff8c9dbbc8 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f085a470000 CR3: 000000000c88e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__queue_work+0x48e/0xee0 kernel/workqueue.c:1461
call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701
expire_timers kernel/time/timer.c:1747 [inline]
__run_timers+0x598/0x810 kernel/time/timer.c:2023
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036
handle_softirqs+0x291/0x910 kernel/softirq.c:596
run_ksoftirqd+0xa4/0x100 kernel/softirq.c:968
smpboot_thread_fn+0x667/0xa30 kernel/smpboot.c:164
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>