rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=8881, q=206) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294975041-4294964538), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.1 R running task 27504 8549 8214 0x00000800 Call Trace: sched_show_task kernel/sched/core.c:5338 [inline] sched_show_task.cold+0x2e2/0x343 kernel/sched/core.c:5313 print_other_cpu_stall kernel/rcu/tree.c:1430 [inline] check_cpu_stall kernel/rcu/tree.c:1557 [inline] __rcu_pending kernel/rcu/tree.c:3293 [inline] rcu_pending kernel/rcu/tree.c:3336 [inline] rcu_check_callbacks.cold+0xaf0/0xddc kernel/rcu/tree.c:2682 update_process_times+0x2a/0x70 kernel/time/timer.c:1638 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168 tick_sched_timer+0x42/0x130 kernel/time/tick-sched.c:1278 __run_hrtimer kernel/time/hrtimer.c:1401 [inline] __hrtimer_run_queues+0x2fc/0xd50 kernel/time/hrtimer.c:1463 hrtimer_interrupt+0x312/0x770 kernel/time/hrtimer.c:1521 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline] smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893 RIP: 0010:check_preemption_disabled+0x33/0x280 lib/smp_processor_id.c:15 Code: 41 54 55 48 89 fd 53 e8 cb ea 11 fe 65 44 8b 25 33 d3 ab 7c 65 8b 1d cc 3f ac 7c 81 e3 ff ff ff 7f 31 ff 89 de e8 1d ec 11 fe <85> db 74 18 e8 a4 ea 11 fe e8 9f ea 11 fe 44 89 e0 5b 5d 41 5c 41 RSP: 0018:ffff88804476f130 EFLAGS: 00000297 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000002 RBX: 0000000000000002 RCX: ffffffff8355ae13 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000005 RBP: ffffffff87ab00c0 R08: ffff8880447643c0 R09: ffffed1015cc4733 R10: ffffed1015cc4732 R11: ffff8880ae623993 R12: 0000000000000000 R13: ffffffff87ab0080 R14: 0000000000004000 R15: ffff88804476f2f8 rcu_lockdep_current_cpu_online kernel/rcu/tree.c:1078 [inline] rcu_lockdep_current_cpu_online+0xb2/0x1b0 kernel/rcu/tree.c:1068 rcu_read_lock_sched_held+0x92/0x130 kernel/rcu/update.c:115 trace_kvm_mmu_paging_element arch/x86/kvm/mmutrace.h:81 [inline] trace_kvm_mmu_paging_element arch/x86/kvm/mmutrace.h:81 [inline] paging64_walk_addr_generic+0xc31/0x2270 arch/x86/kvm/paging_tmpl.h:374 paging64_walk_addr arch/x86/kvm/paging_tmpl.h:483 [inline] paging64_gva_to_gpa+0x9c/0x1c0 arch/x86/kvm/paging_tmpl.h:937 kvm_fetch_guest_virt+0xe4/0x1b0 arch/x86/kvm/x86.c:5014 __do_insn_fetch_bytes+0x3cf/0x640 arch/x86/kvm/emulate.c:896 x86_decode_insn+0x176c/0x5730 arch/x86/kvm/emulate.c:5118 x86_emulate_instruction+0x7b9/0x1b80 arch/x86/kvm/x86.c:6336 kvm_mmu_page_fault+0x2ee/0x1540 arch/x86/kvm/mmu.c:5390 vmx_handle_exit+0x26f/0x16b0 arch/x86/kvm/vmx.c:10199 vcpu_enter_guest+0x10ca/0x5ed0 arch/x86/kvm/x86.c:7850 vcpu_run arch/x86/kvm/x86.c:7913 [inline] kvm_arch_vcpu_ioctl_run+0x446/0x16a0 arch/x86/kvm/x86.c:8113 kvm_vcpu_ioctl+0x493/0xe20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2667 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c479 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:00007f121e5a9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f121e5aa6d4 RCX: 000000000045c479 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 000000000000000a RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000003bf R14: 00000000004c6098 R15: 000000000076bf2c rcu: rcu_preempt kthread starved for 10556 jiffies! g8881 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29152 10 2 0x80000000 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x4d1/0xf20 kernel/time/timer.c:1806 rcu_gp_kthread+0xcee/0x2060 kernel/rcu/tree.c:2202 kthread+0x34a/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415