rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=b16/1/0x4000000000000004 softirq=129375/129375 fqs=1 
	(t=10501 jiffies g=182593 q=90)
rcu: rcu_preempt kthread starved for 10500 jiffies! g182593 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29264    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x934/0x1f90 kernel/sched/core.c:4081
 schedule+0xdc/0x2b0 kernel/sched/core.c:4155
 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0x9b2/0x18d0 kernel/rcu/tree.c:1821
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 23260 Comm: syz-executor.5 Not tainted 5.5.0-rc6-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+0x197/0x210 lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2827 [inline]
 rcu_sched_clock_irq.cold+0x509/0xc0d kernel/rcu/tree.c:2271
 update_process_times+0x2d/0x70 kernel/time/timer.c:1726
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1641
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x4f/0x80 kernel/locking/spinlock.c:199
Code: c0 e8 34 93 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 33 48 83 3d a2 0f bf 01 00 74 20 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 27 65 7c f9 65 8b 05 28 f9 2d 78 85 c0 74 06 41
RSP: 0000:ffffc90000da8dd0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff132669d RBX: ffffffff863b5420 RCX: 0000000000000003
RDX: dffffc0000000000 RSI: ffff8880399e2a40 RDI: ffff8880399e2a14
RBP: ffffc90000da8dd8 R08: 1ffffffff165e7ad R09: fffffbfff165e7ae
R10: fffffbfff165e7ad R11: ffffffff8b2f3d6f R12: ffff8880ae927240
R13: ffff888089d58c18 R14: ffff8880ae927240 R15: dffffc0000000000
 expire_timers kernel/time/timer.c:1448 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x6b1/0x1790 kernel/time/timer.c:1786
 __do_softirq+0x262/0x98c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x19b/0x1e0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:__sanitizer_cov_trace_pc+0x2b/0x50 kernel/kcov.c:190
Code: 48 89 e5 65 48 8b 04 25 c0 1e 02 00 65 8b 15 f4 28 8d 7e 81 e2 00 01 1f 00 48 8b 75 08 75 2b 8b 90 80 13 00 00 83 fa 02 75 20 <48> 8b 88 88 13 00 00 8b 80 84 13 00 00 48 8b 11 48 83 c2 01 48 39
RSP: 0000:ffffc9000841fa88 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: ffff8880399e2180 RBX: 000000004f575067 RCX: ffffffff81a1c60e
RDX: 0000000000000002 RSI: ffffffff81a1c62e RDI: 0000000000000007
RBP: ffffc9000841fa88 R08: ffff8880399e2180 R09: fffff94000062ce1
R10: fffff94000062ce0 R11: ffffea0000316707 R12: 000ffffffffff000
R13: 1ffff92001083f53 R14: 0000000000000001 R15: 000000004f575007
 pmd_pfn+0x12e/0x1d0 arch/x86/include/asm/pgtable.h:222
 pte_lockptr include/linux/mm.h:1902 [inline]
 pte_alloc_one_map mm/memory.c:3316 [inline]
 alloc_set_pte+0xb8e/0x1800 mm/memory.c:3434
 filemap_map_pages+0x11f4/0x14e0 mm/filemap.c:2654
 do_fault_around mm/memory.c:3598 [inline]
 do_read_fault mm/memory.c:3632 [inline]
 do_fault mm/memory.c:3766 [inline]
 handle_pte_fault mm/memory.c:3997 [inline]
 __handle_mm_fault+0x2de6/0x3cc0 mm/memory.c:4127
 handle_mm_fault+0x3b2/0xa50 mm/memory.c:4164
 do_user_addr_fault arch/x86/mm/fault.c:1441 [inline]
 __do_page_fault+0x536/0xd80 arch/x86/mm/fault.c:1506
 do_page_fault+0x38/0x590 arch/x86/mm/fault.c:1530
 page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1203
RIP: 0033:0x443633
Code: 00 00 00 00 00 66 90 66 0f 6e ce 89 f8 25 ff 0f 00 00 66 0f 60 c9 3d c0 0f 00 00 66 0f 61 c9 66 0f 70 c9 00 0f 8f 4d 01 00 00 <f3> 0f 6f 07 66 0f ef db 66 0f 6f e0 66 0f 74 c1 66 0f 74 e3 66 0f
RSP: 002b:00007f784b627408 EFLAGS: 00010287
RAX: 0000000000000f55 RBX: 00007f784b627970 RCX: 00000000fbad8001
RDX: 00007f784b627ae8 RSI: 0000000000000025 RDI: 00000000004bff55
RBP: 00007f784b627960 R08: 0000000000000000 R09: 00007f784b627ae8
R10: 0000000000000003 R11: 0000000000000246 R12: 00000000004bff55
R13: 00007f784b627ae8 R14: 00007f784b627ae8 R15: 0000000000000000