INFO: task syz.5.3498:18477 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.3498 state:D stack:23920 pid:18477 ppid:12859 flags:0x00004006
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
get_signal+0x11a6/0x1350 kernel/signal.c:2648
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: 0033:0x7fa277b9c819
RSP: 002b:00007fa278abbfd8 EFLAGS: 00000202 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffff RBX: 00007fa277e16090 RCX: 00007fa277b9c819
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000002c9a4080
RBP: 00007fa277c32c91 R08: ffffffffff600000 R09: ffffffffff600000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fa277e16128 R14: 00007fa277e16090 R15: 00007ffd2363b2e8
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2df30 (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: ffffffff8cb2e750 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8cb2d5a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2d5a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2d5a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
2 locks held by getty/4036:
#0: ffff88814d628098 (&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
2 locks held by kworker/0:8/4346:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
#1: ffffc900045afd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
5 locks held by kworker/u4:6/4348:
1 lock held by syz.3.4256/21216:
#0: ffff888071bf8210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
#0: ffff888071bf8210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline]
#0: ffff888071bf8210 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1399
1 lock held by syz.6.4270/21269:
#0: ffffffff8cb33278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
#0: ffffffff8cb33278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 16571 Comm: kworker/u4:11 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsrl arch/x86/include/asm/msr.h:262 [inline]
RIP: 0010:native_x2apic_icr_write arch/x86/include/asm/apic.h:239 [inline]
RIP: 0010:__x2apic_send_IPI_dest arch/x86/kernel/apic/x2apic_phys.c:126 [inline]
RIP: 0010:x2apic_send_IPI+0x70/0xd0 arch/x86/kernel/apic/x2apic_phys.c:48
Code: f0 48 c1 e8 03 42 0f b6 04 20 84 c0 75 3b 41 0f b7 16 0f ae f0 0f ae e8 83 fb 02 b8 00 04 00 00 0f 45 c3 b9 30 08 00 00 0f 30 <66> 90 5b 41 5c 41 5e 41 5f 5d c3 89 fe 89 fd 48 c7 c7 c0 90 99 8c
RSP: 0018:ffffc900030b7710 EFLAGS: 00000206
RAX: 00000000000000fb RBX: 00000000000000fb RCX: 0000000000000830
RDX: 0000000000000001 RSI: 00000000000000fb RDI: 0000000000000001
RBP: ffffc900030b77f0 R08: ffff8880b8e3bbd7 R09: 1ffff110171c777a
R10: dffffc0000000000 R11: ffffed10171c777b R12: dffffc0000000000
R13: 1ffff92000616eec R14: ffff8880b8f219b0 R15: ffffffff8c652988
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f790a9e7158 CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
arch_send_call_function_single_ipi arch/x86/include/asm/smp.h:109 [inline]
send_call_function_single_ipi+0x155/0x200 kernel/sched/core.c:3786
smp_call_function_many_cond+0xb5f/0x1290 kernel/smp.c:978
on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1165
on_each_cpu include/linux/smp.h:71 [inline]
text_poke_sync arch/x86/kernel/alternative.c:1574 [inline]
text_poke_bp_batch+0x5ae/0x850 arch/x86/kernel/alternative.c:1836
text_poke_flush arch/x86/kernel/alternative.c:1965 [inline]
text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1972
arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x11f/0x240 kernel/jump_label.c:207
static_key_enable+0x16/0x20 kernel/jump_label.c:220
toggle_allocation_gate+0xba/0x470 mm/kfence/core.c:821
process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295