rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=25661, q=101) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294985459-4294974957), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor.1 R running task 26352 11647 8253 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:arch_local_save_flags arch/x86/include/asm/paravirt.h:784 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/paravirt.h:806 [inline] RIP: 0010:lock_is_held_type+0x6c/0x210 kernel/locking/lockdep.c:3937 Code: 01 00 00 8b 83 7c 08 00 00 85 c0 0f 85 38 01 00 00 48 c7 c0 80 56 b2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 <0f> 85 6a 01 00 00 48 83 3d 06 6a 63 07 00 0f 84 1d 01 00 00 9c 58 RSP: 0018:ffff888041c1f1a0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff1164ad0 RBX: ffff888045570240 RCX: 1ffffffff11f8a30 RDX: dffffc0000000000 RSI: 00000000ffffffff RDI: ffff888045570abc RBP: ffffffff88b92960 R08: ffff888045570240 R09: ffffed10053c619a R10: ffffed10053c6199 R11: ffff888029e30ccb R12: 0000000000000048 R13: ffff888041c1f370 R14: 0000000000004000 R15: ffff888041c1f368 lock_is_held include/linux/lockdep.h:344 [inline] ___might_sleep+0x228/0x2b0 kernel/sched/core.c:6157 __might_fault+0xba/0x1d0 mm/memory.c:4635 __copy_from_user include/linux/uaccess.h:72 [inline] paging64_walk_addr_generic+0x3fd/0x2270 arch/x86/kvm/paging_tmpl.h:370 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_emulate_instruction arch/x86/kvm/x86.c:6451 [inline] handle_ud+0xad/0x290 arch/x86/kvm/x86.c:5148 handle_exception+0x8a8/0xca0 arch/x86/kvm/vmx.c:7087 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: 0033:0x45c4a9 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:00007fa1aef98c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa1aef996d4 RCX: 000000000045c4a9 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006 RBP: 000000000076bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000003bf R14: 00000000004c60e4 R15: 000000000076bfcc rcu: rcu_preempt kthread starved for 10502 jiffies! g25661 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29456 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