INFO: task syz.3.8922:32471 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.8922 state:D stack:25040 pid:32471 ppid:30561 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x107f/0x4030 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+0x176/0x1050 kernel/events/core.c:5037 put_event kernel/events/core.c:5162 [inline] perf_event_release_kernel+0x7c4/0x850 kernel/events/core.c:5287 perf_release+0x37/0x40 kernel/events/core.c:5297 __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:2649 arch_do_signal_or_restart+0xc4/0x1310 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: 0033:0x7f4a76b9ce59 RSP: 002b:00007f4a77a0ffd8 EFLAGS: 00000202 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffff RBX: 00007f4a76e15fa0 RCX: 00007f4a76b9ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000002c9a4080 RBP: 00007f4a76c32e6f R08: ffffffffff600000 R09: ffffffffff600000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007f4a76e16038 R14: 00007f4a76e15fa0 R15: 00007ffd10b42db8 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 2 locks 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: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8cb33838 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962 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:6513 2 locks held by getty/4026: #0: ffff888030261098 (&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 kworker/u4:22/13425: #0: ffff8880b8f3ad18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x25/0x130 kernel/sched/core.c:538 #1: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #1: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #1: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: do_perf_sw_event kernel/events/core.c:9736 [inline] #1: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: ___perf_sw_event+0x184/0x6d0 kernel/events/core.c:9774 #2: ffff8880b8e28458 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x6c1/0xd20 kernel/time/timer.c:1112 #3: ffffffff96e318e0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x68/0x4f0 lib/debugobjects.c:698 2 locks held by kworker/0:6/30774: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 #1: ffffc900035b7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267 1 lock held by syz.5.9778/2692: 3 locks held by syz.5.9837/2898: 1 lock held by syz.4.9847/2925: #0: ffffffff8cb8c828 (bpf_event_mutex){+.+.}-{3:3}, at: perf_event_detach_bpf_prog+0x87/0x310 kernel/trace/bpf_trace.c:2178 1 lock held by syz.0.9850/2942: #0: ffffffff8cb33700 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x5e0 kernel/rcu/tree.c:4023 1 lock held by syz.1.9851/2935: #0: ffffffff8cb8c828 (bpf_event_mutex){+.+.}-{3:3}, at: perf_event_detach_bpf_prog+0x87/0x310 kernel/trace/bpf_trace.c:2178 1 lock held by syz.2.9853/2941: #0: ffffffff8cb8c828 (bpf_event_mutex){+.+.}-{3:3}, at: perf_event_detach_bpf_prog+0x87/0x310 kernel/trace/bpf_trace.c:2178 ============================================= 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 05/09/2026 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2898 Comm: syz.5.9837 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:215 Code: 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d 90 f0 9d 0c 48 89 de 5b e9 77 5d 50 00 00 00 cc cc 00 00 cc 48 8b 04 24 <65> 48 8b 0d 24 4e 80 7e 65 8b 15 25 4e 80 7e 81 e2 00 01 ff 00 74 RSP: 0018:ffffc90003576bd0 EFLAGS: 00000002 RAX: ffffffff81b149a6 RBX: 0000000000080000 RCX: 0000000000000000 RDX: ffff88802b30bc00 RSI: 0000000000000002 RDI: 00000000ffffffff RBP: 0000000000000002 R08: ffffea000136de87 R09: 1ffffd400026dbd0 R10: dffffc0000000000 R11: fffff9400026dbd1 R12: ffff888063792000 R13: 0000000000000002 R14: 00000000ffffffff R15: 0000000000000000 FS: 00007f625bd866c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f16e79e8158 CR3: 0000000099955000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: lru_gen_update_size+0x336/0xea0 include/linux/mm_inline.h:192 lru_gen_add_folio+0x6c2/0xfb0 include/linux/mm_inline.h:261 lruvec_add_folio include/linux/mm_inline.h:322 [inline] lru_add_fn+0x720/0x1890 mm/swap.c:220 folio_batch_move_lru+0x2a4/0x690 mm/swap.c:238 folio_add_lru+0x412/0xcf0 mm/swap.c:526 shmem_get_folio_gfp+0x1750/0x35e0 mm/shmem.c:1976 shmem_get_folio mm/shmem.c:2072 [inline] shmem_write_begin+0xee/0x3f0 mm/shmem.c:2556 generic_perform_write+0x2fa/0x5c0 mm/filemap.c:3862 __generic_file_write_iter+0x148/0x2a0 mm/filemap.c:3960 generic_file_write_iter+0xab/0x2e0 mm/filemap.c:3989 __kernel_write_iter+0x298/0x690 fs/read_write.c:517 dump_emit_page fs/coredump.c:950 [inline] dump_user_range+0x40a/0x840 fs/coredump.c:977 elf_core_dump+0x30ca/0x3630 fs/binfmt_elf.c:2354 do_coredump+0x16c1/0x2480 fs/coredump.c:824 get_signal+0x1093/0x1340 kernel/signal.c:2858 arch_do_signal_or_restart+0xc4/0x1310 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 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:316 exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1485 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 002b:0000200000000248 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f625b215fa0 RCX: 00007f625af9ce59 RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000006800000 RBP: 00007f625b032e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000200000000300 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f625b216038 R14: 00007f625b215fa0 R15: 00007ffd84d77c88