rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 ticks this GP) idle=d5e/1/0x4000000000000004 softirq=32937/32937 fqs=1 (t=29986 jiffies g=54349 q=22073) rcu: rcu_preempt kthread starved for 29985 jiffies! g54349 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 28848 10 2 0x80004000 Call Trace: schedule+0xd0/0x2a0 kernel/sched/core.c:4168 schedule_timeout+0x35c/0x850 kernel/time/timer.c:1898 rcu_gp_fqs_loop kernel/rcu/tree.c:1674 [inline] rcu_gp_kthread+0x9bf/0x1960 kernel/rcu/tree.c:1836 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 0 CPU: 0 PID: 15710 Comm: syz-executor.0 Not tainted 5.6.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x19b/0x1e5 kernel/rcu/tree_stall.h:254 print_cpu_stall kernel/rcu/tree_stall.h:475 [inline] check_cpu_stall kernel/rcu/tree_stall.h:549 [inline] rcu_pending kernel/rcu/tree.c:3225 [inline] rcu_sched_clock_irq.cold+0x55d/0xcfa kernel/rcu/tree.c:2296 update_process_times+0x25/0x60 kernel/time/timer.c:1727 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176 tick_sched_timer+0x4e/0x140 kernel/time/tick-sched.c:1320 __run_hrtimer kernel/time/hrtimer.c:1520 [inline] __hrtimer_run_queues+0x5ca/0xed0 kernel/time/hrtimer.c:1584 hrtimer_interrupt+0x312/0x770 kernel/time/hrtimer.c:1646 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1113 [inline] smp_apic_timer_interrupt+0x15b/0x600 arch/x86/kernel/apic/apic.c:1138 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:__do_softirq+0x22f/0x9f7 kernel/softirq.c:278 Code: c7 c0 70 98 94 89 48 c1 e8 03 42 80 3c 30 00 0f 85 18 07 00 00 48 83 3d 4e 96 94 01 00 0f 84 f1 05 00 00 fb 66 0f 1f 44 00 00 <48> c7 44 24 08 00 91 80 89 b8 ff ff ff ff 0f bc 04 24 83 c0 01 89 RSP: 0018:ffffc90000007f38 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff132930e RBX: ffff88804ac42580 RCX: 1ffffffff186b1e9 RDX: 0000000000000000 RSI: ffff88804ac42e70 RDI: ffff88804ac42e44 RBP: 0000000000000025 R08: 0000000000000001 R09: fffffbfff185c15e R10: ffffffff8c2e0aef R11: fffffbfff185c15d R12: 0000000000000025 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x192/0x1d0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:546 [inline] do_IRQ+0xda/0x270 arch/x86/kernel/irq.c:263 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:607 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline] RIP: 0010:lock_acquire+0x267/0x8f0 kernel/locking/lockdep.c:4926 Code: 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 c6 05 00 00 48 83 3d f5 20 3b 08 00 0f 84 65 04 00 00 48 8b 3c 24 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 03 44 24 08 48 c7 RSP: 0018:ffffc900087e7be0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffffda RAX: 1ffffffff132930c RBX: ffff88804ac42580 RCX: ffffffff81591e55 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000286 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8c2e0ae7 R11: fffffbfff185c15c R12: 0000000000000002 R13: ffffc9000886afc8 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:208 [inline] srcu_read_lock include/linux/srcu.h:155 [inline] vcpu_run arch/x86/kvm/x86.c:8565 [inline] kvm_arch_vcpu_ioctl_run+0x646/0x16a0 arch/x86/kvm/x86.c:8756 kvm_vcpu_ioctl+0x493/0xe60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3138 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x11a/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:770 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45c889 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f3b1f01fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f3b1f0206d4 RCX: 000000000045c889 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000007 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000003be R14: 00000000004c64be R15: 000000000076bf0c