rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=62129, q=53) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294999232-4294988730), jiffies_till_next_fqs=1, root ->qsmask 0x0 syz-executor0 R running task 21936 21282 5532 0x00000000 Call Trace: sched_show_task.cold.83+0x2b6/0x30a kernel/sched/core.c:5296 print_other_cpu_stall.cold.79+0xa83/0xba5 kernel/rcu/tree.c:1430 check_cpu_stall kernel/rcu/tree.c:1557 [inline] __rcu_pending kernel/rcu/tree.c:3276 [inline] rcu_pending kernel/rcu/tree.c:3319 [inline] rcu_check_callbacks+0xafc/0x1990 kernel/rcu/tree.c:2665 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+0x41c/0x10d0 kernel/time/hrtimer.c:1460 hrtimer_interrupt+0x313/0x780 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline] smp_apic_timer_interrupt+0x1a1/0x760 arch/x86/kernel/apic/apic.c:1054 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864 RIP: 0010:kvm_cpu_has_pending_timer+0x51/0x70 arch/x86/kvm/lapic.h:160 Code: 55 8a 66 00 89 d8 5b 5d c3 e8 4b 8a 66 00 48 8d bb e0 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <75> 16 48 83 bb e0 03 00 00 00 75 ba e8 1e 8a 66 00 31 db 89 d8 5b RSP: 0018:ffff880165ec7848 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: ffff88018a861240 RCX: ffffc900036d8000 RDX: 1ffff1003150c2c4 RSI: ffffffff81184675 RDI: ffff88018a861620 RBP: ffff880165ec7850 R08: ffff8801bcaa6580 R09: 1ffffffff12b43d5 R10: ffff880165ec7860 R11: ffff8801daf23993 R12: ffff88018a861270 R13: 0000000000000007 R14: 0000000000000007 R15: dffffc0000000000 vcpu_run arch/x86/kvm/x86.c:7720 [inline] kvm_arch_vcpu_ioctl_run+0x3a6/0x16e0 arch/x86/kvm/x86.c:7888 kvm_vcpu_ioctl+0x72b/0x1150 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2590 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702 __do_sys_ioctl fs/ioctl.c:709 [inline] __se_sys_ioctl fs/ioctl.c:707 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457099 Code: fd b4 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 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f660ab60c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f660ab616d4 RCX: 0000000000457099 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006 RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004cf730 R14: 00000000004c59b9 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10502 jiffies! g62129 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 22872 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 schedule_timeout+0x140/0x260 kernel/time/timer.c:1804 rcu_gp_kthread+0x9d9/0x2310 kernel/rcu/tree.c:2194 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 sched: RT throttling activated audit: type=1400 audit(1536517384.531:208): avc: denied { map } for pid=21309 comm="syz-executor5" path="/sys/kernel/debug/kcov" dev="debugfs" ino=1103 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:debugfs_t:s0 tclass=file permissive=1 IPVS: ftp: loaded support on port[0] = 21 audit: type=1400 audit(1536517384.631:209): avc: denied { map } for pid=21311 comm="sh" path="/bin/dash" dev="sda1" ino=1473 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21 IPVS: ftp: loaded support on port[0] = 21