rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=32a/1/0x4000000000000000 softirq=96736/96749 fqs=1 
	(t=10500 jiffies g=184449 q=174)
rcu: rcu_preempt kthread starved for 10498 jiffies! g184449 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I29640    10      2 0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3445 [inline]
 __schedule+0x8b4/0x1e80 kernel/sched/core.c:4169
 schedule+0xd0/0x2a0 kernel/sched/core.c:4244
 schedule_timeout+0x148/0x250 kernel/time/timer.c:1897
 rcu_gp_fqs_loop kernel/rcu/tree.c:1871 [inline]
 rcu_gp_kthread+0xae5/0x1b50 kernel/rcu/tree.c:2041
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
NMI backtrace for cpu 0
CPU: 0 PID: 25180 Comm: syz-executor.0 Not tainted 5.8.0-rc5-next-20200714-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:165 [inline]
 rcu_dump_cpu_stacks+0x194/0x1cf kernel/rcu/tree_stall.h:318
 print_cpu_stall kernel/rcu/tree_stall.h:551 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:625 [inline]
 rcu_pending kernel/rcu/tree.c:3626 [inline]
 rcu_sched_clock_irq.cold+0x5b3/0xcbd kernel/rcu/tree.c:2509
 update_process_times+0x25/0x60 kernel/time/timer.c:1726
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:176
 tick_sched_timer+0x108/0x290 kernel/time/tick-sched.c:1328
 __run_hrtimer kernel/time/hrtimer.c:1520 [inline]
 __hrtimer_run_queues+0x1d5/0xfc0 kernel/time/hrtimer.c:1584
 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1079 [inline]
 __sysvec_apic_timer_interrupt+0x142/0x5e0 arch/x86/kernel/apic/apic.c:1096
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline]
 sysvec_apic_timer_interrupt+0x4f/0x120 arch/x86/kernel/apic/apic.c:1090
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:587
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:765 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x8c/0xe0 kernel/locking/spinlock.c:191
Code: 48 c7 c0 00 02 b5 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 37 48 83 3d 3b 06 c6 01 00 74 22 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 b5 9c 60 f9 65 8b 05 9e 02 13 78
RSP: 0018:ffffc90000007c30 EFLAGS: 00000286
RAX: 1ffffffff136a040 RBX: 0000000000000286 RCX: 0000000000000002
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000286
RBP: ffff8880ae6255c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880ae6255c0
R13: 000000010001cc2d R14: 000000010001cc31 R15: 0000000000000000
 __mod_timer+0x669/0xf40 kernel/time/timer.c:1057
 pie_timer+0x13e/0x180 net/sched/sch_pie.c:434
 call_timer_fn+0x1ac/0x760 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers.part.0+0x54c/0xa20 kernel/time/timer.c:1773
 __run_timers kernel/time/timer.c:1745 [inline]
 run_timer_softirq+0xae/0x1a0 kernel/time/timer.c:1786
 __do_softirq+0x34c/0xa60 kernel/softirq.c:292
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 do_softirq_own_stack+0x111/0x170 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:387 [inline]
 __irq_exit_rcu kernel/softirq.c:417 [inline]
 irq_exit_rcu+0x229/0x270 kernel/softirq.c:429
 sysvec_apic_timer_interrupt+0x54/0x120 arch/x86/kernel/apic/apic.c:1090
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:587
RIP: 0010:__split_huge_pmd_locked mm/huge_memory.c:2090 [inline]
RIP: 0010:__split_huge_pmd+0x180c/0x4020 mm/huge_memory.c:2205
Code: ff 4c 89 e2 48 8b 7c 24 28 48 89 d9 48 8b 74 24 30 e8 a8 15 7c ff 66 90 be 04 00 00 00 4c 89 ef e8 09 c5 fc ff f0 41 ff 45 00 <83> 44 24 40 01 bf 00 02 00 00 49 83 c5 40 8b 5c 24 40 48 81 44 24
RSP: 0018:ffffc900052379f0 EFLAGS: 00000256
RAX: 0000000000000001 RBX: 0000000020d34827 RCX: ffffffff81b6eb77
RDX: fffff940001069a7 RSI: 0000000000000004 RDI: ffffea0000834d30
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffea0000834d33
R10: fffff940001069a6 R11: 0000000000000000 R12: ffff8880456ad9a0
R13: ffffea0000834d30 R14: 0000000000000000 R15: 00000000456ad067
 split_huge_pmd_address+0x229/0x290 mm/huge_memory.c:2248
 vma_adjust_trans_huge+0x262/0x2f0 mm/huge_memory.c:2274
 __vma_adjust+0x18f/0x23e0 mm/mmap.c:794
 vma_adjust include/linux/mm.h:2482 [inline]
 __split_vma+0x2bd/0x560 mm/mmap.c:2731
 __do_munmap+0x322/0x1170 mm/mmap.c:2818
 mremap_to mm/mremap.c:565 [inline]
 __do_sys_mremap+0x103a/0x12c0 mm/mremap.c:698
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cba9
Code: Bad RIP value.
RSP: 002b:00007f6dbe37bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000019
RAX: ffffffffffffffda RBX: 00000000004f8820 RCX: 000000000045cba9
RDX: 0000000000800000 RSI: 0000000000001000 RDI: 0000000020a96000
RBP: 000000000078c0e0 R08: 0000000020130000 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000007a6 R14: 00000000004ca90b R15: 00007f6dbe37c6d4