rcu: INFO: rcu_sched self-detected stall on CPU
rcu: 	0-....: (10500 ticks this GP) idle=446/1/0x4000000000000002 softirq=42783/42783 fqs=5241 
	(t=10502 jiffies g=57881 q=1595)
NMI backtrace for cpu 0
CPU: 0 PID: 9631 Comm: syz-executor.5 Not tainted 5.2.0+ #37
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+0x1d8/0x2f8 /lib/dump_stack.c:113
 nmi_cpu_backtrace+0xb0/0x1a0 /lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x14c/0x240 /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:2736 [inline]
 rcu_sched_clock_irq+0x7e3/0xfb0 /kernel/rcu/tree.c:2183
 update_process_times+0x114/0x170 /kernel/time/timer.c:1639
 tick_sched_handle /kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x257/0x410 /kernel/time/tick-sched.c:1296
 __run_hrtimer /kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x471/0x8c0 /kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x36c/0xd80 /kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt /arch/x86/kernel/apic/apic.c:1068 [inline]
 smp_apic_timer_interrupt+0xc2/0x220 /arch/x86/kernel/apic/apic.c:1093
 apic_timer_interrupt+0xf/0x20 /arch/x86/entry/entry_64.S:828
 </IRQ>
RIP: 0010:arch_local_irq_restore /./arch/x86/include/asm/paravirt.h:768 [inline]
RIP: 0010:lock_acquire+0x1b2/0x250 /kernel/locking/lockdep.c:4416
Code: c1 e8 03 42 80 3c 30 00 74 0c 48 c7 c7 80 87 ca 88 e8 a2 7c 55 00 48 83 3d 7a e7 6e 07 00 0f 84 9c 00 00 00 48 8b 7d c0 57 9d <0f> 1f 44 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 44 89
RSP: 0018:ffff8880a857e960 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11950f0 RBX: 0000000000000000 RCX: ffffffff815baf26
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000282
RBP: ffff8880a857e9b8 R08: dffffc0000000000 R09: fffffbfff13bc09d
R10: fffffbfff13bc09d R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: ffffffff88cd6380
 rcu_lock_acquire+0x1d/0x30 /./include/linux/rcupdate.h:208
 rcu_read_lock /./include/linux/rcupdate.h:592 [inline]
 mem_cgroup_iter+0xe6/0xa70 /mm/memcontrol.c:1033
 shrink_node+0x364/0x17a0 /mm/vmscan.c:2675
 shrink_zones+0x2d8/0x940 /mm/vmscan.c:2940
 do_try_to_free_pages+0x21e/0x930 /mm/vmscan.c:2998
 try_to_free_mem_cgroup_pages+0x3d1/0x6c0 /mm/vmscan.c:3300
 try_charge+0x6aa/0x17b0 /mm/memcontrol.c:2399
 __memcg_kmem_charge_memcg+0x78/0x180 /mm/memcontrol.c:2781
 memcg_kmem_charge_memcg /./include/linux/memcontrol.h:1314 [inline]
 memcg_charge_slab /mm/slab.h:304 [inline]
 charge_slab_page /mm/slab.h:425 [inline]
 kmem_getpages+0x411/0x970 /mm/slab.c:1372
 cache_grow_begin+0x7e/0x2c0 /mm/slab.c:2599
 fallback_alloc+0x134/0x1c0 /mm/slab.c:3146
 ____cache_alloc_node+0x22a/0x250 /mm/slab.c:3214
 __do_cache_alloc /mm/slab.c:3283 [inline]
 slab_alloc /mm/slab.c:3311 [inline]
 kmem_cache_alloc+0x157/0x2e0 /mm/slab.c:3483
 ext4_alloc_inode+0x1f/0x560 /fs/ext4/super.c:1073
 alloc_inode /fs/inode.c:227 [inline]
 iget_locked+0x182/0x8a0 /fs/inode.c:1181
 __ext4_iget+0x2f0/0x47b0 /fs/ext4/inode.c:4866
 ext4_lookup+0x61f/0xd30 /fs/ext4/namei.c:1700
 __lookup_slow+0x2d8/0x410 /fs/namei.c:1669
 lookup_slow /fs/namei.c:1686 [inline]
 mountpoint_last /fs/namei.c:2663 [inline]
 path_mountpoint+0x29f/0x750 /fs/namei.c:2693
 filename_mountpoint+0x221/0x670 /fs/namei.c:2715
 user_path_mountpoint_at+0x39/0x50 /fs/namei.c:2745
 ksys_umount+0x169/0x10a0 /fs/namespace.c:1680
 __do_sys_umount /fs/namespace.c:1706 [inline]
 __se_sys_umount /fs/namespace.c:1704 [inline]
 __x64_sys_umount+0x5a/0x70 /fs/namespace.c:1704
 do_syscall_64+0xfe/0x140 /arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c247
Code: 64 89 04 25 d0 02 00 00 58 5f ff d0 48 89 c7 e8 2f be ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 9d 8d fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffd11d907c8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045c247
RDX: 0000000000403470 RSI: 0000000000000002 RDI: 00007ffd11d90870
RBP: 00000000000004e6 R08: 0000000000000000 R09: 000000000000000c
R10: 0000000000000006 R11: 0000000000000206 R12: 00007ffd11d91900
R13: 000055555678a940 R14: 0000000000000000 R15: 00007ffd11d91900