rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=29996 jiffies, g=331669, q=215) rcu: All QSes seen, last rcu_preempt kthread activity 29996 (4295180599-4295150603), jiffies_till_next_fqs=1, root ->qsmask 0x0 kworker/1:0 R running task 28120 6477 2 0x80000008 Workqueue: rcu_gp process_srcu Call Trace: sched_show_task kernel/sched/core.c:5306 [inline] sched_show_task.cold+0x292/0x30b kernel/sched/core.c:5281 print_other_cpu_stall kernel/rcu/tree.c:1301 [inline] check_cpu_stall kernel/rcu/tree.c:1429 [inline] rcu_pending kernel/rcu/tree.c:3018 [inline] rcu_check_callbacks.cold+0xa10/0xa4a kernel/rcu/tree.c:2521 update_process_times+0x32/0x80 kernel/time/timer.c:1635 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:161 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1271 __run_hrtimer kernel/time/hrtimer.c:1389 [inline] __hrtimer_run_queues+0x33e/0xde0 kernel/time/hrtimer.c:1451 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1035 [inline] smp_apic_timer_interrupt+0x120/0x570 arch/x86/kernel/apic/apic.c:1060 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807 RIP: 0010:ffs arch/x86/include/asm/bitops.h:424 [inline] RIP: 0010:__do_softirq+0x227/0x95a kernel/softirq.c:280 Code: c7 c0 00 83 92 88 48 c1 e8 03 42 80 3c 38 00 0f 85 37 07 00 00 48 83 3d e6 80 52 01 00 0f 84 f4 05 00 00 fb 66 0f 1f 44 00 00 ff ff ff ff 48 c7 45 c8 00 91 80 88 0f bc 45 d4 83 c0 01 89 45 RSP: 0018:ffff8880ae907f10 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff1125060 RBX: ffff8880873a8580 RCX: 1ffff11010e751ce RDX: 0000000000000000 RSI: ffff8880873a8e50 RDI: ffff8880873a8dfc RBP: ffff8880ae907f98 R08: ffff8880873a8580 R09: ffff8880873a8e70 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88805b317b08 R13: 0000000000000021 R14: 0000000000000021 R15: dffffc0000000000 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x180/0x1d0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] do_IRQ+0x114/0x1d0 arch/x86/kernel/irq.c:258 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:583 RIP: 0010:rdtsc arch/x86/include/asm/msr.h:207 [inline] RIP: 0010:rdtsc_ordered arch/x86/include/asm/msr.h:232 [inline] RIP: 0010:delay_tsc+0x4c/0xc0 arch/x86/lib/delay.c:61 Code: e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00 e8 63 f6 4c fa e8 7e 34 2a fc 44 39 e8 75 36 0f ae e8 0f 31 <48> c1 e2 20 48 89 d3 48 09 c3 48 89 d8 4c 29 e0 4c 39 f0 73 24 bf RSP: 0018:ffff88805b317bb0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde RAX: 000000001a020cc0 RBX: 0000051a1a020ba0 RCX: ffffffff832b086a RDX: 000000000000051a RSI: ffffffff832b0878 RDI: 0000000000000005 RBP: ffff88805b317bd0 R08: ffff8880873a8580 R09: 0000000000000040 R10: 0000000000000040 R11: ffffffff88a41827 R12: 0000051a1a01f5c5 R13: 0000000000000001 R14: 0000000000002ced R15: 0000000000002d34 __delay arch/x86/lib/delay.c:161 [inline] __const_udelay+0x5f/0x80 arch/x86/lib/delay.c:175 try_check_zero+0x201/0x330 kernel/rcu/srcutree.c:730 srcu_advance_state kernel/rcu/srcutree.c:1167 [inline] process_srcu+0x329/0xec0 kernel/rcu/srcutree.c:1261 process_one_work+0x98e/0x1790 kernel/workqueue.c:2173 worker_thread+0x98/0xe40 kernel/workqueue.c:2319 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 rcu: rcu_preempt kthread starved for 29996 jiffies! g331669 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29440 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2844 [inline] __schedule+0x817/0x1cc0 kernel/sched/core.c:3485 schedule+0x92/0x180 kernel/sched/core.c:3529 schedule_timeout+0x4db/0xfd0 kernel/time/timer.c:1803 rcu_gp_fqs_loop kernel/rcu/tree.c:1948 [inline] rcu_gp_kthread+0x956/0x17a0 kernel/rcu/tree.c:2105 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352