rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=b3e/1/0x4000000000000002 softirq=10870/10870 fqs=1 
	(t=10500 jiffies g=6309 q=315)
rcu: rcu_preempt kthread starved for 10498 jiffies! g6309 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29104    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 8179 Comm: syz-executor.0 Not tainted 5.4.0-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+0x1fb/0x318 lib/dump_stack.c:118
 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15a/0x220 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+0xe25/0x1ad0 kernel/rcu/tree.c:2271
 update_process_times+0x12d/0x180 kernel/time/timer.c:1726
 tick_sched_handle kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1638
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:memcg_kmem_uncharge include/linux/memcontrol.h:1402 [inline]
RIP: 0010:free_thread_stack+0x124/0x590 kernel/fork.c:284
Code: ff 48 c1 e8 06 48 83 e0 c0 48 bf 00 00 00 00 00 ea ff ff 48 01 c7 be 03 00 00 00 e8 06 a2 60 00 e9 5d 04 00 00 e8 5c 2d 2e 00 <48> 89 df 31 f6 e8 42 af 6e 00 43 80 3c 2e 00 74 08 4c 89 e7 e8 43
RSP: 0018:ffffc900023e7818 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffffffff81486ea4 RBX: ffffea0001b0ce40 RCX: ffff88809540c240
RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea0001b0ce40
RBP: ffffc900023e7850 R08: 000000000003a768 R09: ffffed10150f274f
R10: ffffed10150f274f R11: 0000000000000000 R12: ffff8880988950a0
R13: dffffc0000000000 R14: 1ffff11013112a14 R15: ffff8880a8793a68
 release_task_stack kernel/fork.c:440 [inline]
 put_task_stack+0xa3/0x130 kernel/fork.c:451
 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256
 context_switch kernel/sched/core.c:3388 [inline]
 __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081
 preempt_schedule_irq+0xc1/0x140 kernel/sched/core.c:4338
 retint_kernel+0x1b/0x2b
RIP: 0010:trace_mm_page_alloc+0x0/0x1f0 include/trace/events/kmem.h:193
Code: c2 d0 4e bf 88 8b 4d 84 31 c0 e8 9b be ff ff eb a3 0f 0b e9 7a d9 ff ff e8 0d 13 9f ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 <55> 48 89 e5 41 57 41 56 41 55 41 54 53 50 89 4d d0 89 55 d4 49 be
RSP: 0000:ffffc900023e7a60 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffff9200047cf00 RBX: ffffea0001bf8e00 RCX: 0000000000000001
RDX: 0000000000100dca RSI: 0000000000000000 RDI: ffffea0001bf8e00
RBP: ffffc900023e7af0 R08: ffffffff81b169ec R09: ffffed100dfc7000
R10: fffff9400037f1c7 R11: 0000000000000000 R12: 1ffff9200047cf57
R13: dffffc0000000000 R14: 0000000000100dca R15: 0000000000000000
 alloc_pages_vma+0x4f7/0xd50 mm/mempolicy.c:2170
 alloc_zeroed_user_highpage_movable include/linux/highmem.h:208 [inline]
 wp_page_copy+0x1e2/0x1ca0 mm/memory.c:2404
 do_wp_page+0x5e4/0x16d0 mm/memory.c:2662
 handle_pte_fault mm/memory.c:3961 [inline]
 __handle_mm_fault mm/memory.c:4075 [inline]
 handle_mm_fault+0x23c5/0x2890 mm/memory.c:4112
 do_user_addr_fault+0x589/0xaf0 arch/x86/mm/fault.c:1441
 __do_page_fault+0xd3/0x1f0 arch/x86/mm/fault.c:1506
 do_page_fault+0x99/0xb0 arch/x86/mm/fault.c:1530
 page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1203
RIP: 0033:0x40f6c8
Code: 8b 34 c6 4a 8d 04 2e 48 3d ff ff ff 7e 0f 86 77 ff ff ff bf 64 fe 4b 00 31 c0 e8 13 27 ff ff 31 ff e8 5c 23 ff ff 0f 1f 40 00 <89> 3c b5 00 00 73 00 eb b6 31 ed 0f 1f 44 00 00 80 3d 7e 2f 66 00
RSP: 002b:00007ffdc69756e0 EFLAGS: 00010246
RAX: 00000000817c3a0f RBX: 00000000bace1edf RCX: 0000001b32720000
RDX: 0000000000000000 RSI: 0000000000001a0f RDI: ffffffff817c3a0f
RBP: 0000000000000000 R08: 00000000817c3a0f R09: 00000000817c3a13
R10: 00007ffdc6975880 R11: 0000000000000246 R12: 000000000075bfa8
R13: 0000000080000000 R14: 00007f9f4f585008 R15: 0000000000000000