INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=1970, c=1969, q=144) All QSes seen, last rcu_preempt kthread activity 10502 (4294970312-4294959810), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.4 R running task 27616 7827 7415 0x00000800 Call Trace: sched_show_task kernel/sched/core.c:5168 [inline] sched_show_task.cold+0x2e3/0x347 kernel/sched/core.c:5143 print_other_cpu_stall kernel/rcu/tree.c:1501 [inline] check_cpu_stall kernel/rcu/tree.c:1616 [inline] __rcu_pending kernel/rcu/tree.c:3390 [inline] rcu_pending kernel/rcu/tree.c:3452 [inline] rcu_check_callbacks.cold+0xd3f/0xdaa kernel/rcu/tree.c:2792 update_process_times+0x29/0x60 kernel/time/timer.c:1590 tick_sched_handle+0x7d/0x150 kernel/time/tick-sched.c:165 tick_sched_timer+0x3e/0x120 kernel/time/tick-sched.c:1223 __run_hrtimer kernel/time/hrtimer.c:1223 [inline] __hrtimer_run_queues+0x25c/0xbb0 kernel/time/hrtimer.c:1287 hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline] smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100 apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792 RIP: 0010:vcpu_enter_guest+0xd66/0x5240 arch/x86/kvm/x86.c:7297 RSP: 0018:ffff88804e11fae0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10 RAX: 0000000000040000 RBX: ffff88804e1140c0 RCX: ffffc90009640000 RDX: 0000000000040000 RSI: ffffffff810a3a8f RDI: ffff88804e11493c RBP: ffff88804e11fbe0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88804e1a0100 R13: ffff88804e1a01e0 R14: ffff88804e1a0128 R15: ffffff8476fc6c08 vcpu_run arch/x86/kvm/x86.c:7379 [inline] kvm_arch_vcpu_ioctl_run+0x2fe/0xfd0 arch/x86/kvm/x86.c:7546 kvm_vcpu_ioctl+0x3df/0xc70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2661 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c4a9 RSP: 002b:00007f875123dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f875123e6d4 RCX: 000000000045c4a9 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000007 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000003bf R14: 00000000004c60e4 R15: 000000000076bf2c rcu_preempt kthread starved for 10502 jiffies! g1970 c1969 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=1 rcu_preempt R running task 29920 8 2 0x80000000 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_timeout+0x43c/0xe40 kernel/time/timer.c:1746 rcu_gp_kthread+0xb8e/0x1ce0 kernel/rcu/tree.c:2255 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404