INFO: task syz.1.1528:10661 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1528 state:D stack:24176 pid:10661 ppid:4272 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5246 [inline] __schedule+0x107f/0x4030 kernel/sched/core.c:6563 schedule+0xb9/0x180 kernel/sched/core.c:6639 perf_pending_task_sync kernel/events/core.c:5041 [inline] _free_event+0x176/0x1050 kernel/events/core.c:5047 put_event kernel/events/core.c:5172 [inline] perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5297 perf_release+0x37/0x40 kernel/events/core.c:5307 __fput+0x20a/0x8b0 fs/file_table.c:320 task_work_run+0x1d0/0x260 kernel/task_work.c:203 get_signal+0x118d/0x1340 kernel/signal.c:2661 arch_do_signal_or_restart+0xc4/0x1310 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:213 __syscall_exit_to_user_mode_work kernel/entry/common.c:295 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:306 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f6976b9e1d9 RSP: 002b:00007f6974df5fd8 EFLAGS: 00000202 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffff RBX: 00007f6976e25fa0 RCX: 00007f6976b9e1d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000002c9a4080 RBP: 00007f6976c35888 R08: ffffffffff600000 R09: ffffffffff600000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007f6976e26038 R14: 00007f6976e25fa0 R15: 00007ffd65999328 Showing all locks held in the system: 2 locks held by kworker/u4:0/9: #0: ffff8880b8c3acd8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x25/0x130 kernel/sched/core.c:538 #1: ffffffff8d92d8a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #1: ffffffff8d92d8a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #1: ffffffff8d92d8a0 (rcu_read_lock){....}-{1:2}, at: do_perf_sw_event kernel/events/core.c:9746 [inline] #1: ffffffff8d92d8a0 (rcu_read_lock){....}-{1:2}, at: ___perf_sw_event+0x184/0x6d0 kernel/events/core.c:9784 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d92e230 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 2 locks held by rcu_tasks_trace/13: #0: ffffffff8d92ea50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517 #1: ffffffff8d933578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8d933578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962 2 locks held by kworker/1:0/22: #0: ffff888018472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #1: ffffc900001c7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 1 lock held by khungtaskd/27: #0: ffffffff8d92d8a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d92d8a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d92d8a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6669 2 locks held by getty/4029: #0: ffff88814d516098 (&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 4 locks held by syz.3.2497/14739: 1 lock held by syz.5.2508/14771: #0: ffffffff8d98c788 (bpf_event_mutex){+.+.}-{3:3}, at: perf_event_detach_bpf_prog+0x87/0x310 kernel/trace/bpf_trace.c:2178 2 locks held by syz.3.2510/14779: #0: ffff8880550a1410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:764 [inline] #0: ffff8880550a1410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline] #0: ffff8880550a1410 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1400 #1: ffffffff8d933578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8d933578 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962 1 lock held by syz.5.2513/14784: #0: ffffffff8d98c788 (bpf_event_mutex){+.+.}-{3:3}, at: perf_event_detach_bpf_prog+0x87/0x310 kernel/trace/bpf_trace.c:2178 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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+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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 9 Comm: kworker/u4:0 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:pmd_alloc include/linux/mm.h:2430 [inline] RIP: 0010:walk_to_pmd+0xdd/0x240 mm/memory.c:1833 Code: 07 48 21 c8 48 89 d9 48 c1 e9 1e 81 e1 ff 01 00 00 4c 8d 3c c8 49 01 d7 0f 84 d7 00 00 00 4d 89 fc 49 c1 ec 03 43 80 3c 2c 00 <74> 08 4c 89 ff e8 19 22 14 00 49 8b 2f 48 89 ee 48 83 e6 9f 31 ff RSP: 0018:ffffc900000e77f0 EFLAGS: 00000246 RAX: 0000000018464000 RBX: 00002aaaaaaab000 RCX: 00000000000000aa RDX: ffff888000000000 RSI: 0000000018464007 RDI: 0000000000000000 RBP: 0000000018464007 R08: ffffea0000074b07 R09: 1ffffd400000e960 R10: dffffc0000000000 R11: fffff9400000e961 R12: 1ffff1100308c8aa R13: dffffc0000000000 R14: ffff888018468000 R15: ffff888018464550 FS: 0000000000000000(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f83d87ef158 CR3: 000000000d68e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000200000000340 DR3: 0000200000000340 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __get_locked_pte+0x23/0x1b0 mm/memory.c:1844 get_locked_pte include/linux/mm.h:2308 [inline] __text_poke+0x231/0x840 arch/x86/kernel/alternative.c:1395 text_poke arch/x86/kernel/alternative.c:1480 [inline] text_poke_bp_batch+0x6b5/0x850 arch/x86/kernel/alternative.c:1852 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+0x8ab/0x1160 kernel/workqueue.c:2292 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295