INFO: task syz.3.16:2856 blocked for more than 143 seconds. Not tainted 6.5.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.16 state:D stack:13968 pid:2856 ppid:2402 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x3ff/0xa80 kernel/sched/core.c:6710 schedule+0x59/0xb0 kernel/sched/core.c:6786 coredump_task_exit kernel/exit.c:436 [inline] do_exit+0xfd/0xb80 kernel/exit.c:823 do_group_exit+0x32/0xa0 kernel/exit.c:1024 get_signal+0xae6/0xaf0 kernel/signal.c:2877 arch_do_signal_or_restart+0x39/0x280 arch/x86/kernel/signal.c:308 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0xc3/0x150 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x17/0x40 kernel/entry/common.c:297 do_syscall_64+0x4c/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x6f/0xd9 RIP: 0033:0x7f715adab929 RSP: 002b:00007ffc02f429b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffdfc RBX: 000000000000d49d RCX: 00007f715adab929 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f715afd308c RBP: 0000000000000032 R08: 0000000000000001 R09: 0000000602f42caf R10: 00007ffc02f42ab0 R11: 0000000000000246 R12: 00007f715afd308c R13: 00007ffc02f42ab0 R14: 000000000000d4cf R15: 00007ffc02f42ad0 INFO: task syz.3.16:2858 blocked for more than 144 seconds. Not tainted 6.5.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.16 state:D stack:14144 pid:2858 ppid:2402 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x3ff/0xa80 kernel/sched/core.c:6710 schedule+0x59/0xb0 kernel/sched/core.c:6786 schedule_timeout+0x137/0x150 kernel/time/timer.c:2143 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion_state+0x14a/0x210 kernel/sched/completion.c:254 coredump_wait fs/coredump.c:414 [inline] do_coredump+0x2e1/0x1810 fs/coredump.c:571 get_signal+0x9d3/0xaf0 kernel/signal.c:2863 arch_do_signal_or_restart+0x39/0x280 arch/x86/kernel/signal.c:308 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0xc3/0x150 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x17/0x40 kernel/entry/common.c:297 do_syscall_64+0x4c/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x6f/0xd9 RIP: 0033:0x7f715adab929 RSP: 002b:00007f715a67a0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 00000000000000ca RBX: 00007f715afd3088 RCX: 00007f715adab929 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f715afd308c RBP: 00007f715afd3080 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f715afd308c R13: 0000000000000000 R14: 00007ffc02f42770 R15: 00007ffc02f42858 Showing all locks held in the system: 2 locks held by kworker/u4:0/10: #0: ffff888100070938 ((wq_completion)events_unbound){....}-{0:0}, at: wake_up_worker kernel/workqueue.c:898 [inline] #0: ffff888100070938 ((wq_completion)events_unbound){....}-{0:0}, at: process_one_work+0x1ff/0x4f0 kernel/workqueue.c:2559 #1: ffffc9000005be58 ((work_completion)(&(&kfence_timer)->work)){....}-{0:0}, at: wake_up_worker kernel/workqueue.c:898 [inline] #1: ffffc9000005be58 ((work_completion)(&(&kfence_timer)->work)){....}-{0:0}, at: process_one_work+0x1ff/0x4f0 kernel/workqueue.c:2559 1 lock held by rcu_tasks_kthre/13: #0: ffffffff8257b610 (rcu_tasks.tasks_gp_mutex){....}-{3:3}, at: rcu_tasks_one_gp+0x26/0x3c0 kernel/rcu/tasks.h:522 1 lock held by khungtaskd/27: #0: ffffffff8257bcc0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x12/0x120 kernel/locking/lockdep.c:6615 2 locks held by getty/808: #0: ffff888101e6f898 (&tty->ldisc_sem){....}-{0:0}, at: tty_ldisc_ref_wait+0x23/0x60 drivers/tty/tty_ldisc.c:243 #1: ffffc900003fb2f0 (&ldata->atomic_read_lock){....}-{3:3}, at: n_tty_read+0x513/0x650 drivers/tty/n_tty.c:2187 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 6.5.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x3d/0x70 lib/dump_stack.c:106 nmi_cpu_backtrace+0xd4/0x110 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x11c/0x140 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0x5e2/0x620 kernel/hung_task.c:379 kthread+0xde/0x110 kernel/kthread.c:389 ret_from_fork+0x2c/0x50 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:296 RIP: 0000:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2857 Comm: syz.3.16 Not tainted 6.5.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:get_lock_parent_ip include/linux/ftrace.h:986 [inline] RIP: 0010:preempt_latency_start kernel/sched/core.c:5834 [inline] RIP: 0010:preempt_latency_start kernel/sched/core.c:5831 [inline] RIP: 0010:preempt_count_add+0x73/0x90 kernel/sched/core.c:5859 Code: 6f 03 00 85 c0 75 1a 65 48 8b 04 25 80 bf 02 00 48 89 98 c0 13 00 00 48 83 c4 08 5b c3 cc cc cc cc 31 ff 31 db e8 2d 6f 03 00 db 89 7c 24 04 90 e8 e1 f9 4c 00 90 8b 7c 24 04 eb 9f 66 2e 0f RSP: 0018:ffffc900016f3e10 EFLAGS: 00000003 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffc900016f3db4 RDX: 0000000000000001 RSI: ffffc900016f3ec0 RDI: 0000000000000000 RBP: 0000000000000202 R08: ffff888109294488 R09: ffffc900016f3e10 R10: 0000000000080000 R11: 0000000000000000 R12: ffff888109294460 R13: ffff888109294000 R14: 0000000000000000 R15: ffffc900016f3ed8 FS: 00007f715a81c6c0(0000) GS:ffff888237d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc5636772f0 CR3: 0000000104ff8000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:109 [inline] _raw_spin_lock_irqsave+0x16/0x50 kernel/locking/spinlock.c:162 prepare_to_wait_exclusive+0x29/0xb0 kernel/sched/wait.c:285 io_cqring_wait io_uring/io_uring.c:2572 [inline] __do_sys_io_uring_enter+0x79a/0xc10 io_uring/io_uring.c:3655 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3c/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x6f/0xd9 RIP: 0033:0x7f715adab929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007f715a81c038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007f715afd2fa0 RCX: 00007f715adab929 RDX: 000000000000235c RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f715ae2db39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f715afd2fa0 R15: 00007ffc02f42858