rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P29/2:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=12165, q=749 ncpus=2)
task:ktimers/1       state:R  running task     stack:26016 pid:29    tgid:29    ppid:2      task_flags:0x4208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0x1553/0x5240 kernel/sched/core.c:6911
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7095
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 class_preempt_destructor include/linux/preempt.h:468 [inline]
 raw_spin_unlock_irqrestore_wake include/linux/sched/wake_q.h:102 [inline]
 rtlock_slowlock kernel/locking/rtmutex.c:1896 [inline]
 rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
 __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
 rt_spin_lock+0x316/0x400 kernel/locking/spinlock_rt.c:57
 spin_lock include/linux/spinlock_rt.h:45 [inline]
 class_spinlock_irqsave_constructor include/linux/spinlock.h:618 [inline]
 snd_seq_check_queue+0xb5/0x580 sound/core/seq/seq_queue.c:241
 snd_timer_process_callbacks sound/core/timer.c:785 [inline]
 snd_timer_interrupt+0x10a8/0x1360 sound/core/timer.c:901
 snd_hrtimer_callback+0x213/0x3a0 sound/core/hrtimer.c:51
 __run_hrtimer kernel/time/hrtimer.c:1785 [inline]
 __hrtimer_run_queues+0x55f/0xda0 kernel/time/hrtimer.c:1849
 hrtimer_run_softirq+0x192/0x5d0 kernel/time/hrtimer.c:1866
 handle_softirqs+0x1de/0x6f0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 run_ktimerd+0x69/0x100 kernel/softirq.c:1138
 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>