netlink: 7 bytes leftover after parsing attributes in process `syz-executor4'. INFO: rcu_sched detected stalls on CPUs/tasks: (detected by 1, t=125007 jiffies, g=38407, c=38406, q=5) All QSes seen, last rcu_sched kthread activity 125014 (4295020493-4294895479), jiffies_till_next_fqs=3, root ->qsmask 0x0 syz-executor2 R running task 24600 17912 4541 0x00000008 Call Trace: sched_show_task.cold.86+0x27a/0x301 kernel/sched/core.c:5325 print_other_cpu_stall.cold.79+0x92f/0x9d2 kernel/rcu/tree.c:1481 check_cpu_stall.isra.61+0x706/0xf50 kernel/rcu/tree.c:1599 __rcu_pending kernel/rcu/tree.c:3356 [inline] rcu_pending kernel/rcu/tree.c:3401 [inline] rcu_check_callbacks+0x21b/0xad0 kernel/rcu/tree.c:2763 update_process_times+0x2d/0x70 kernel/time/timer.c:1636 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274 __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0x3e3/0x10a0 kernel/time/hrtimer.c:1460 hrtimer_interrupt+0x2f3/0x750 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1025 [inline] smp_apic_timer_interrupt+0x15d/0x710 arch/x86/kernel/apic/apic.c:1050 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863 RIP: 0010:echo_buf drivers/tty/n_tty.c:144 [inline] RIP: 0010:__process_echoes+0x1fd/0x8d0 drivers/tty/n_tty.c:733 RSP: 0018:ffff8801bc81f7e0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000040000 RBX: 00000001a7745556 RCX: ffffc900040d9000 RDX: 0000000000040000 RSI: ffffffff8397b46d RDI: 0000000000000001 RBP: ffff8801bc81f848 R08: ffff8801865a0740 R09: 0000000000000006 R10: ffff8801865a0740 R11: 0000000000000000 R12: ffffc90001ae0000 R13: 0000000000000189 R14: 00000001a7745557 R15: 00000000000000ff flush_echoes drivers/tty/n_tty.c:799 [inline] __receive_buf drivers/tty/n_tty.c:1615 [inline] n_tty_receive_buf_common+0x11d5/0x2c50 drivers/tty/n_tty.c:1709 n_tty_receive_buf+0x30/0x40 drivers/tty/n_tty.c:1738 tiocsti drivers/tty/tty_io.c:2171 [inline] tty_ioctl+0x7e7/0x1870 drivers/tty/tty_io.c:2557 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x1cf/0x16a0 fs/ioctl.c:684 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701 __do_sys_ioctl fs/ioctl.c:708 [inline] __se_sys_ioctl fs/ioctl.c:706 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455979 RSP: 002b:00007f1d12fdcc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f1d12fdd6d4 RCX: 0000000000455979 RDX: 00000000200000c0 RSI: 0000000000005412 RDI: 0000000000000014 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000033e R14: 00000000006f8e70 R15: 0000000000000000 rcu_sched kthread starved for 125593 jiffies! g38407 c38406 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=1 RCU grace-period kthread stack dump: rcu_sched R running task 23592 9 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2848 [inline] __schedule+0x801/0x1e30 kernel/sched/core.c:3490 schedule+0xef/0x430 kernel/sched/core.c:3549 schedule_timeout+0x138/0x240 kernel/time/timer.c:1801 rcu_gp_kthread+0x6b5/0x1940 kernel/rcu/tree.c:2231 kthread+0x345/0x410 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412