rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=6833, q=109) rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294953997-4294943494), jiffies_till_next_fqs=1, root ->qsmask 0x0 blkid R running task 28312 8293 8242 0x80004008 Call Trace: sched_show_task+0x40f/0x560 kernel/sched/core.c:5954 print_other_cpu_stall kernel/rcu/tree_stall.h:410 [inline] check_cpu_stall kernel/rcu/tree_stall.h:538 [inline] rcu_pending kernel/rcu/tree.c:2827 [inline] rcu_sched_clock_irq+0x1861/0x1ad0 kernel/rcu/tree.c:2271 update_process_times+0x12d/0x180 kernel/time/timer.c:1726 tick_sched_handle kernel/time/tick-sched.c:167 [inline] tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310 __run_hrtimer kernel/time/hrtimer.c:1517 [inline] __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:check_kcov_mode kernel/kcov.c:79 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x22/0x50 kernel/kcov.c:102 Code: d4 01 3b 00 5b 5d c3 cc 48 8b 04 24 65 48 8b 0c 25 c0 1d 02 00 65 8b 15 38 84 8b 7e f7 c2 00 01 1f 00 75 2c 8b 91 80 13 00 00 <83> fa 02 75 21 48 8b 91 88 13 00 00 48 8b 32 48 8d 7e 01 8b 89 84 RSP: 0018:ffffc90002657870 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffffffff81487326 RBX: ffffea0002449240 RCX: ffff8880942c4680 RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea0002449240 RBP: ffffc90002657898 R08: 000000000003a728 R09: ffffed101239032f R10: ffffed101239032f R11: 0000000000000000 R12: ffff8880912a1420 R13: dffffc0000000000 R14: 00000000fffffffc R15: ffff888091c81968 free_thread_stack+0x168/0x590 kernel/fork.c:280 release_task_stack kernel/fork.c:440 [inline] put_task_stack+0xa3/0x130 kernel/fork.c:451 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256 context_switch kernel/sched/core.c:3388 [inline] __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081 preempt_schedule_irq+0xc1/0x140 kernel/sched/core.c:4338 retint_kernel+0x1b/0x2b RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline] RIP: 0010:kmem_cache_free+0xc8/0xf0 mm/slab.c:3695 Code: 58 07 00 74 42 4c 89 f7 57 9d 0f 1f 44 00 00 e8 4e 99 ca ff eb 19 e8 e7 96 ca ff 48 83 3d 17 f9 58 07 00 74 24 4c 89 f7 57 9d <0f> 1f 44 00 00 4c 89 e7 4c 89 fe e8 58 01 00 00 5b 41 5c 41 5e 41 RSP: 0018:ffffc90002657af0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: ffff8880942c4f14 RBX: ffff88821bc46700 RCX: ffffffff815c0407 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000286 RBP: ffffc90002657b10 R08: ffff8880942c4ed8 R09: fffffbfff13ca12d R10: fffffbfff13ca12d R11: 0000000000000000 R12: ffffffff81a705c0 R13: ffff8880944e5e20 R14: 0000000000000286 R15: ffff888093b2db60 anon_vma_chain_free mm/rmap.c:135 [inline] unlink_anon_vmas+0x310/0x690 mm/rmap.c:421 free_pgtables+0x1ae/0x300 mm/memory.c:413 exit_mmap+0x28a/0x530 mm/mmap.c:3141 __mmput+0x120/0x3a0 kernel/fork.c:1082 mmput+0x5d/0x70 kernel/fork.c:1103 exit_mm+0x50a/0x590 kernel/exit.c:485 do_exit+0x544/0x2020 kernel/exit.c:784 do_group_exit+0x15c/0x2b0 kernel/exit.c:895 __do_sys_exit_group+0x17/0x20 kernel/exit.c:906 __se_sys_exit_group+0x14/0x20 kernel/exit.c:904 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:904 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f39c14cf1e8 Code: Bad RIP value. RSP: 002b:00007ffd2c5d7378 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f39c14cf1e8 RDX: 0000000000000002 RSI: 000000000000003c RDI: 0000000000000002 RBP: 00007f39c17a4840 R08: 00000000000000e7 R09: ffffffffffffffa8 R10: 00007f39c17aa740 R11: 0000000000000246 R12: 00007f39c17a4840 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10543 jiffies! g6833 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29104 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081 schedule+0x181/0x210 kernel/sched/core.c:4155 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline] rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352