rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P28/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=13813, q=43582 ncpus=2)
task:rcuc/1          state:R  running task     stack:25976 pid:28    tgid:28    ppid:2      task_flags:0x4208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5504 [inline]
 __schedule+0x16dc/0x5500 kernel/sched/core.c:7228
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7552
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
Code: cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 57 56 52 51 50 41 50 41 51 41 52 41 53 e8 4a 96 f3 09 <41> 5b 41 5a 41 59 41 58 58 59 5a 5e 5f 5d c3 cc cc cc cc 90 90 90
RSP: 0018:ffffc90000a2fb70 EFLAGS: 00000246
RAX: 1ffff11003ad7ba0 RBX: 0000000000000292 RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8ba92960 RDI: ffffffff8ba92920
RBP: ffffc90000a2fbb8 R08: ffffffff8f8abcf7 R09: 1ffffffff1f1579e
R10: dffffc0000000000 R11: fffffbfff1f1579f R12: 0000000000000001
R13: dffffc0000000000 R14: ffffffff99abe4e0 R15: ffffffff81ab469b
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
 _raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:198
 debug_rcu_head_unqueue kernel/rcu/rcu.h:245 [inline]
 rcu_do_batch kernel/rcu/tree.c:2637 [inline]
 rcu_core kernel/rcu/tree.c:2897 [inline]
 rcu_cpu_kthread+0x8c9/0x1480 kernel/rcu/tree.c:2985
 smpboot_thread_fn+0x57c/0xa80 kernel/smpboot.c:160
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>