INFO: task syz.2.323:5499 blocked for more than 143 seconds. Not tainted 6.1.137-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.323 state:D stack:24320 pid:5499 ppid:4286 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5244 [inline] __schedule+0x10e9/0x40d0 kernel/sched/core.c:6561 schedule+0xb9/0x180 kernel/sched/core.c:6637 perf_pending_task_sync kernel/events/core.c:5033 [inline] _free_event+0x171/0x10a0 kernel/events/core.c:5039 put_event kernel/events/core.c:5164 [inline] perf_event_release_kernel+0x832/0x8c0 kernel/events/core.c:5289 perf_release+0x37/0x40 kernel/events/core.c:5299 __fput+0x22c/0x920 fs/file_table.c:320 task_work_run+0x1ca/0x250 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x936/0x2400 kernel/exit.c:871 do_group_exit+0x217/0x2d0 kernel/exit.c:1021 get_signal+0x1272/0x1350 kernel/signal.c:2871 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 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:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fc49198e969 RSP: 002b:00007fc492782fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffff4 RBX: 00007fc491bb5fa0 RCX: 00007fc49198e969 RDX: 0000000000000000 RSI: 000000000003fff0 RDI: 00000000630c1000 RBP: 00007fc491a10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc491bb5fa0 R15: 00007ffe3797abf8 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8c92b2f0 (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: ffffffff8c92bb10 (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: ffffffff8c92a960 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8c92a960 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8c92a960 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 2 locks held by getty/4007: #0: ffff888030813098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198 2 locks held by kworker/u4:2/4324: 1 lock held by syz.4.922/7300: 2 locks held by syz.4.965/7421: 2 locks held by syz.1.974/7444: 5 locks held by syz.5.988/7486: 3 locks held by syz.1.990/7502: 2 locks held by syz.0.1003/7539: #0: ffffffff8c97fb68 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 #1: ffffffff8c930638 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8c930638 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x455/0x830 kernel/rcu/tree_exp.h:962 1 lock held by syz.4.1002/7540: #0: ffffffff8c97fb68 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.137-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3f4/0x470 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: 5598 Comm: syz-executor Not tainted 6.1.137-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:969 [inline] RIP: 0010:debug_check_no_obj_freed+0x1ca/0x530 lib/debugobjects.c:1009 Code: 00 00 48 ba 00 00 00 00 00 fc ff df ff c3 48 8b 04 24 48 89 c5 48 85 c0 0f 84 3a 03 00 00 49 89 ee 49 c1 ee 03 41 80 3c 16 00 <74> 12 48 89 ef e8 2c 40 c6 fd 48 ba 00 00 00 00 00 fc ff df 48 8b RSP: 0018:ffffc9000511f650 EFLAGS: 00000046 RAX: 1ffffffff2d8e647 RBX: 0000000000000000 RCX: dffffc0000000000 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc9000511f540 RBP: ffff88802c8afe00 R08: 0000000000000004 R09: 0000000000000003 R10: fffff52000a23ea8 R11: 1ffff92000a23ea8 R12: ffff88803b37f000 R13: ffff88803b37e000 R14: 1ffff11005915fc0 R15: 0000000000000001 FS: 000055556e1ca500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff53b32efc CR3: 000000007b26c000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: free_pages_prepare mm/page_alloc.c:1465 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x2a6/0x9a0 mm/page_alloc.c:3384 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3525 release_pages+0x1f92/0x2200 mm/swap.c:1035 __pagevec_release+0x6d/0xe0 mm/swap.c:1055 pagevec_release include/linux/pagevec.h:71 [inline] folio_batch_release include/linux/pagevec.h:135 [inline] shmem_undo_range+0x75b/0x2050 mm/shmem.c:946 shmem_truncate_range mm/shmem.c:1062 [inline] shmem_evict_inode+0x248/0xa40 mm/shmem.c:1171 evict+0x485/0x870 fs/inode.c:705 do_unlinkat+0x377/0x560 fs/namei.c:4397 __do_sys_unlink fs/namei.c:4438 [inline] __se_sys_unlink fs/namei.c:4436 [inline] __x64_sys_unlink+0x45/0x50 fs/namei.c:4436 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f211bb8df17 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff53b32ee8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f211bb8df17 RDX: 00007fff53b32f10 RSI: 00007fff53b32fa0 RDI: 00007fff53b32fa0 RBP: 00007fff53b32fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000206 R12: 00007fff53b34030 R13: 00007f211bc1089d R14: 000000000009e300 R15: 00007fff53b34070