syzbot

INFO: rcu_preempt detected stalls on CPUs/tasks:
	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3297
	(detected by 1, t=10502 jiffies, g=4983, c=4982, q=728)
syz-executor816 R  running task    28744  3297   2103 0x00000004
 ffff8801db707c90 ffffffff81400b61 ffffffff81400960 ffff8801d2e05f00
 ffff8801d2e05f00 ffffffff830d6b40 0000000000000096 ffff8801d2e062e0
 dffffc0000000000 ffff8801db707cc8 ffffffff8140b67c 0000000000001376
Call Trace:
 <IRQ> [  436.010158]  [<0000000054464131>] sched_show_task.cold+0x27f/0x327 kernel/sched/core.c:5312
 [<000000009a558528>] rcu_print_detail_task_stall_rnp+0xc2/0xfe kernel/rcu/tree_plugin.h:530
 [<0000000002d5a835>] rcu_print_detail_task_stall kernel/rcu/tree_plugin.h:543 [inline]
 [<0000000002d5a835>] print_other_cpu_stall kernel/rcu/tree.c:1408 [inline]
 [<0000000002d5a835>] check_cpu_stall kernel/rcu/tree.c:1520 [inline]
 [<0000000002d5a835>] __rcu_pending kernel/rcu/tree.c:3495 [inline]
 [<0000000002d5a835>] rcu_pending kernel/rcu/tree.c:3559 [inline]
 [<0000000002d5a835>] rcu_check_callbacks.cold+0x761/0xd2f kernel/rcu/tree.c:2888
 [<000000003a7b9238>] update_process_times+0x31/0x70 kernel/time/timer.c:1629
 [<0000000092bebf43>] tick_sched_handle.isra.0+0x4a/0xf0 kernel/time/tick-sched.c:151
 [<00000000acd299a8>] tick_sched_timer+0x7a/0x130 kernel/time/tick-sched.c:1190
 [<000000002946f652>] __run_hrtimer kernel/time/hrtimer.c:1255 [inline]
 [<000000002946f652>] __hrtimer_run_queues+0x313/0xe00 kernel/time/hrtimer.c:1319
 [<0000000023d6c0ef>] hrtimer_interrupt+0x1b6/0x450 kernel/time/hrtimer.c:1353
 [<000000008b30e044>] local_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:937
 [<00000000e12e241b>] smp_apic_timer_interrupt+0x79/0xb0 arch/x86/kernel/apic/apic.c:961
 [<0000000099e5e184>] apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:650
 <EOI> [  436.114113]  [<00000000f74dc7d7>] ? arch_local_irq_enable arch/x86/include/asm/paravirt.h:778 [inline]
 <EOI> [  436.114113]  [<00000000f74dc7d7>] ? __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:170 [inline]
 <EOI> [  436.114113]  [<00000000f74dc7d7>] ? _raw_spin_unlock_irq+0x2f/0x60 kernel/locking/spinlock.c:199
 [<000000008560263c>] __schedule+0x107b/0x1f10 kernel/sched/core.c:3494
 [<0000000051d03dfd>] preempt_schedule_irq+0x5e/0xa0 kernel/sched/core.c:3704
 [<000000002c1f62e8>] retint_kernel+0x1b/0x2d
 [<0000000001ea8570>] preempt_schedule+0x26/0x30 kernel/sched/core.c:3627
 [<00000000c136e84f>] ___preempt_schedule+0x16/0x18
 [<0000000053f56bb1>] __sched_setscheduler+0x1cd0/0x3060 kernel/sched/core.c:4400
 [<00000000ba267cb2>] sched_setattr kernel/sched/core.c:4442 [inline]
 [<00000000ba267cb2>] SYSC_sched_setattr kernel/sched/core.c:4616 [inline]
 [<00000000ba267cb2>] SyS_sched_setattr+0x25c/0x3d0 kernel/sched/core.c:4595
 [<00000000c3e4a6e6>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288
 [<00000000272d1e6d>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
syz-executor816 R  running task    28744  3297   2103 0x80000004
 ffff8801db707c90 ffffffff81400b61 ffffffff81400960 ffff8801d2e05f00
 ffff8801d2e05f00 ffffffff830d6b40 0000000000000096 ffff8801d2e062e0
 dffffc0000000000 ffff8801db707cc8 ffffffff8140b67c ffffffff830d6ec0
Call Trace:
 <IRQ> [  436.291008]  [<0000000054464131>] sched_show_task.cold+0x27f/0x327 kernel/sched/core.c:5312
 [<000000009a558528>] rcu_print_detail_task_stall_rnp+0xc2/0xfe kernel/rcu/tree_plugin.h:530
 [<00000000f379d8a2>] rcu_print_detail_task_stall kernel/rcu/tree_plugin.h:545 [inline]
 [<00000000f379d8a2>] print_other_cpu_stall kernel/rcu/tree.c:1408 [inline]
 [<00000000f379d8a2>] check_cpu_stall kernel/rcu/tree.c:1520 [inline]
 [<00000000f379d8a2>] __rcu_pending kernel/rcu/tree.c:3495 [inline]
 [<00000000f379d8a2>] rcu_pending kernel/rcu/tree.c:3559 [inline]
 [<00000000f379d8a2>] rcu_check_callbacks.cold+0x7b9/0xd2f kernel/rcu/tree.c:2888
 [<000000003a7b9238>] update_process_times+0x31/0x70 kernel/time/timer.c:1629
 [<0000000092bebf43>] tick_sched_handle.isra.0+0x4a/0xf0 kernel/time/tick-sched.c:151
 [<00000000acd299a8>] tick_sched_timer+0x7a/0x130 kernel/time/tick-sched.c:1190
 [<000000002946f652>] __run_hrtimer kernel/time/hrtimer.c:1255 [inline]
 [<000000002946f652>] __hrtimer_run_queues+0x313/0xe00 kernel/time/hrtimer.c:1319
 [<0000000023d6c0ef>] hrtimer_interrupt+0x1b6/0x450 kernel/time/hrtimer.c:1353
 [<000000008b30e044>] local_apic_timer_interrupt+0x76/0xa0 arch/x86/kernel/apic/apic.c:937
 [<00000000e12e241b>] smp_apic_timer_interrupt+0x79/0xb0 arch/x86/kernel/apic/apic.c:961
 [<0000000099e5e184>] apic_timer_interrupt+0x9d/0xb0 arch/x86/entry/entry_64.S:650
 <EOI> [  436.394757]  [<00000000f74dc7d7>] ? arch_local_irq_enable arch/x86/include/asm/paravirt.h:778 [inline]
 <EOI> [  436.394757]  [<00000000f74dc7d7>] ? __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:170 [inline]
 <EOI> [  436.394757]  [<00000000f74dc7d7>] ? _raw_spin_unlock_irq+0x2f/0x60 kernel/locking/spinlock.c:199
 [<000000008560263c>] __schedule+0x107b/0x1f10 kernel/sched/core.c:3494
 [<0000000051d03dfd>] preempt_schedule_irq+0x5e/0xa0 kernel/sched/core.c:3704
 [<000000002c1f62e8>] retint_kernel+0x1b/0x2d
 [<0000000001ea8570>] preempt_schedule+0x26/0x30 kernel/sched/core.c:3627
 [<00000000c136e84f>] ___preempt_schedule+0x16/0x18
 [<0000000053f56bb1>] __sched_setscheduler+0x1cd0/0x3060 kernel/sched/core.c:4400
 [<00000000ba267cb2>] sched_setattr kernel/sched/core.c:4442 [inline]
 [<00000000ba267cb2>] SYSC_sched_setattr kernel/sched/core.c:4616 [inline]
 [<00000000ba267cb2>] SyS_sched_setattr+0x25c/0x3d0 kernel/sched/core.c:4595
 [<00000000c3e4a6e6>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288
 [<00000000272d1e6d>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb