INFO: task syz.4.284:5310 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.284 state:D stack:24016 pid:5310 ppid:4317 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
schedule+0xb9/0x180 kernel/sched/core.c:6638
perf_pending_task_sync kernel/events/core.c:5031 [inline]
_free_event+0x171/0x10a0 kernel/events/core.c:5037
put_event kernel/events/core.c:5162 [inline]
perf_event_release_kernel+0x83e/0x8d0 kernel/events/core.c:5287
perf_release+0x37/0x40 kernel/events/core.c:5297
__fput+0x22c/0x920 fs/file_table.c:320
task_work_run+0x1d0/0x260 kernel/task_work.c:203
exit_task_work include/linux/task_work.h:39 [inline]
do_exit+0x982/0x2480 kernel/exit.c:880
do_group_exit+0x217/0x2d0 kernel/exit.c:1022
get_signal+0x1272/0x1350 kernel/signal.c:2871
arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8e1859acb9
RSP: 002b:00007f8e19480028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: fffffffffffffff4 RBX: 00007f8e18815fa0 RCX: 00007f8e1859acb9
RDX: 0000000000000048 RSI: 0000200000000580 RDI: 0000000000000000
RBP: 00007f8e18608bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8e18816038 R14: 00007f8e18815fa0 R15: 00007ffffb210858
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2dfb0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2e7d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
2 locks held by kworker/1:1/26:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc90000a1fd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
1 lock held by khungtaskd/28:
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2d620 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by getty/4027:
#0: ffff88814ce3e098 (&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+0x429/0x1390 drivers/tty/n_tty.c:2198
3 locks held by kworker/1:5/4401:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc90004a27d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#2: ffff888079aab240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x270/0x3450 drivers/net/netdevsim/fib.c:1491
4 locks held by kworker/u4:21/5515:
#0: ffff888017616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc9000c80fd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#2: ffffffff8dd38f50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:594
#3: ffffffff8cb332f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#3: ffffffff8cb332f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962
5 locks held by syz-executor/7907:
#0: ffff88807e122460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x26b/0xa30 fs/read_write.c:580
#1: ffff8880271ebc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e3/0x520 fs/kernfs/file.c:343
#2: ffff888144fb2918 (kn->active#53){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888144fb2918 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x236/0x520 fs/kernfs/file.c:344
#3: ffffffff8d6554a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd4/0x360 drivers/net/netdevsim/bus.c:209
#4: ffff8880279750e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline]
#4: ffff8880279750e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1080 [inline]
#4: ffff8880279750e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb2/0x850 drivers/base/dd.c:1283
2 locks held by syz.5.1174/8041:
#0: ffffffff8cb826a8 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
#1: ffffffff8cb332f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
#1: ffffffff8cb332f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962
1 lock held by cmp/8056:
=============================================
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 10/25/2025
Call Trace:
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+0xeee/0xf30 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8042 Comm: syz.5.1174 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4748 [inline]
RIP: 0010:__lock_acquire+0x942/0x7d10 kernel/locking/lockdep.c:4999
Code: 89 c6 41 81 e6 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 40 32 af 90 be 08 00 00 00 e8 46 10 6f 00 4c 0f a3 35 8e e3 4a 0f <73> 1a 4b 8d 04 76 c1 e0 06 4c 8d b0 00 b1 47 90 49 b8 00 00 00 00
RSP: 0018:ffffc90003667040 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81644eaa
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90af3270
RBP: ffffc90003667290 R08: ffffffff90af3277 R09: 1ffffffff215e64e
R10: dffffc0000000000 R11: fffffbfff215e64f R12: ffff88802c524680
R13: ffff88802c524604 R14: 000000000000019e R15: ffff88802c524680
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7aa90a9fe8 CR3: 0000000029424000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
rcu_read_lock include/linux/rcupdate.h:791 [inline]
page_ext_get+0x3a/0x2a0 mm/page_ext.c:157
page_table_check_clear+0x4a/0x6b0 mm/page_table_check.c:71
ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
zap_pte_range mm/memory.c:1433 [inline]
zap_pmd_range mm/memory.c:1572 [inline]
zap_pud_range mm/memory.c:1601 [inline]
zap_p4d_range mm/memory.c:1622 [inline]
unmap_page_range+0x192d/0x2500 mm/memory.c:1643
unmap_vmas+0x260/0x390 mm/memory.c:1728
exit_mmap+0x20d/0x960 mm/mmap.c:3250
__mmput+0x118/0x3c0 kernel/fork.c:1205
exit_mm+0x1fe/0x2d0 kernel/exit.c:565
do_exit+0x905/0x2480 kernel/exit.c:867
do_group_exit+0x217/0x2d0 kernel/exit.c:1022
get_signal+0x1272/0x1350 kernel/signal.c:2871
arch_do_signal_or_restart+0xc4/0x1350 arch/x86/kernel/signal.c:871
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbdecf9acb9
Code: Unable to access opcode bytes at 0x7fbdecf9ac8f.
RSP: 002b:00007fbdede15028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: fffffffffffffff5 RBX: 00007fbded215fa0 RCX: 00007fbdecf9acb9
RDX: 0000000000000048 RSI: 0000200000000200 RDI: 0000000000000005
RBP: 00007fbded008bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbded216038 R14: 00007fbded215fa0 R15: 00007fff14c63aa8