rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1):
	(detected by 1, t=10503 jiffies, g=446697, q=2724)
rcu: All QSes seen, last rcu_preempt kthread activity 7518 (4295238093-4295230575), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 7518 jiffies! g446697 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=143939
rcu: rcu_preempt kthread starved for 7521 jiffies! g446697 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:28864 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:4683 [inline]
 __schedule+0x93a/0x26f0 kernel/sched/core.c:5940
 schedule+0xd3/0x270 kernel/sched/core.c:6019
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1878
 rcu_gp_fqs_loop kernel/rcu/tree.c:1996 [inline]
 rcu_gp_kthread+0xd34/0x1980 kernel/rcu/tree.c:2169
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 26733 Comm: syz-executor.5 Not tainted 5.14.0-rc2-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:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_check_gp_kthread_starvation.cold+0x1d1/0x1d6 kernel/rcu/tree_stall.h:479
 print_other_cpu_stall kernel/rcu/tree_stall.h:584 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:709 [inline]
 rcu_pending kernel/rcu/tree.c:3922 [inline]
 rcu_sched_clock_irq+0x2001/0x20c0 kernel/rcu/tree.c:2641
 update_process_times+0x16d/0x200 kernel/time/timer.c:1782
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421
 __run_hrtimer kernel/time/hrtimer.c:1537 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1601
 hrtimer_interrupt+0x330/0xa00 kernel/time/hrtimer.c:1663
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1089 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1106
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:page_remove_file_rmap mm/rmap.c:1254 [inline]
RIP: 0010:page_remove_rmap+0x663/0x1480 mm/rmap.c:1348
Code: ff 48 c7 c6 80 a9 96 89 48 89 ef e8 97 29 f9 ff 0f 0b e8 30 6c c6 ff 31 ff 44 89 ee e8 66 72 c6 ff 45 84 ed 0f 85 c4 03 00 00 <e8> 18 6c c6 ff 48 89 ef e8 20 2e 07 00 31 ff 89 c3 89 c6 e8 45 73
RSP: 0018:ffffc9001cb77760 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888159011c40
RDX: 0000000000000000 RSI: ffff888159011c40 RDI: 0000000000000003
RBP: ffffea0001b18a40 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff81af1caa R11: 0000000000000000 R12: ffffea0001b18a48
R13: 0000000000000000 R14: 0000000000000000 R15: 00007f39cff58000
 zap_pte_range mm/memory.c:1362 [inline]
 zap_pmd_range mm/memory.c:1481 [inline]
 zap_pud_range mm/memory.c:1510 [inline]
 zap_p4d_range mm/memory.c:1531 [inline]
 unmap_page_range+0xed5/0x2a10 mm/memory.c:1552
 unmap_single_vma+0x198/0x300 mm/memory.c:1597
 unmap_vmas+0x16d/0x2f0 mm/memory.c:1629
 exit_mmap+0x1d0/0x620 mm/mmap.c:3201
 __mmput+0x122/0x470 kernel/fork.c:1101
 mmput+0x58/0x60 kernel/fork.c:1122
 exit_mm kernel/exit.c:501 [inline]
 do_exit+0xae2/0x2a60 kernel/exit.c:812
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x47f/0x2160 kernel/signal.c:2808
 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665e9
Code: Unable to access opcode bytes at RIP 0x4665bf.
RSP: 002b:00007f39cf633218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000056bf88 RCX: 00000000004665e9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf88
RBP: 000000000056bf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf8c
R13: 0000000000a9fb1f R14: 00007f39cf633300 R15: 0000000000022000