rcu: INFO: rcu_sched self-detected stall on CPU
rcu: 	1-....: (10499 ticks this GP) idle=b36/1/0x4000000000000002 softirq=115901/115901 fqs=5216 
	(t=10500 jiffies g=215313 q=438)
NMI backtrace for cpu 1
CPU: 1 PID: 29661 Comm: syz-executor.4 Not tainted 5.2.0+ #71
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+0x16f/0x1f0 /lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x70/0xb2 /lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x22d/0x25c /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:2736 [inline]
 rcu_sched_clock_irq.cold+0x491/0x8c0 /kernel/rcu/tree.c:2183
 update_process_times+0x32/0x80 /kernel/time/timer.c:1639
 tick_sched_handle+0xa2/0x190 /kernel/time/tick-sched.c:167
 tick_sched_timer+0x47/0x130 /kernel/time/tick-sched.c:1296
 __run_hrtimer /kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x364/0xd90 /kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x2ea/0x730 /kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt /arch/x86/kernel/apic/apic.c:1068 [inline]
 smp_apic_timer_interrupt+0x10b/0x550 /arch/x86/kernel/apic/apic.c:1093
 apic_timer_interrupt+0xf/0x20 /arch/x86/entry/entry_64.S:828
 </IRQ>
RIP: 0010:debug_lockdep_rcu_enabled+0x38/0xa0 /kernel/rcu/update.c:236
Code: 00 fc ff df 48 89 c1 83 e0 07 48 89 e5 48 c1 e9 03 83 c0 03 0f b6 14 11 38 d0 7c 04 84 d2 75 49 8b 15 0c 43 46 08 85 d2 74 3b <48> c7 c0 34 d9 a4 89 48 ba 00 00 00 00 00 fc ff df 48 89 c1 83 e0
RSP: 0018:ffff88805ff971b8 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000003 RBX: ffff88805ff972b8 RCX: 1ffffffff1349504
RDX: 0000000000000002 RSI: ffffffff81945926 RDI: 0000000000000001
RBP: ffff88805ff971b8 R08: ffff8880966b8340 R09: fffffbfff13494e8
R10: fffffbfff13494e7 R11: ffffffff89a4a73f R12: 1ffff1100bff2e3b
R13: 0000000000000001 R14: ffff88812fffc000 R15: 0000000000000000
 trace_mm_vmscan_memcg_reclaim_begin /./include/trace/events/vmscan.h:130 [inline]
 try_to_free_mem_cgroup_pages+0x6e9/0xa00 /mm/vmscan.c:3295
 try_charge+0x648/0x1430 /mm/memcontrol.c:2399
 __memcg_kmem_charge_memcg+0x71/0xf0 /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 /mm/slab.c:1372 [inline]
 cache_grow_begin+0x601/0xc90 /mm/slab.c:2599
 fallback_alloc+0x1fd/0x2d0 /mm/slab.c:3146
 ____cache_alloc_node+0x1bc/0x1d0 /mm/slab.c:3214
 __do_cache_alloc /mm/slab.c:3283 [inline]
 slab_alloc /mm/slab.c:3311 [inline]
 kmem_cache_alloc+0x1e8/0x700 /mm/slab.c:3483
 ext4_alloc_inode+0x1f/0x640 /fs/ext4/super.c:1073
 alloc_inode+0x68/0x1e0 /fs/inode.c:227
 iget_locked+0x1a6/0x4b0 /fs/inode.c:1181
 __ext4_iget+0x265/0x3d10 /fs/ext4/inode.c:4866
 ext4_lookup /fs/ext4/namei.c:1700 [inline]
 ext4_lookup+0x3b1/0x7a0 /fs/ext4/namei.c:1675
 __lookup_slow+0x279/0x500 /fs/namei.c:1669
 lookup_slow+0x58/0x80 /fs/namei.c:1686
 mountpoint_last /fs/namei.c:2663 [inline]
 path_mountpoint+0x5d2/0x1e60 /fs/namei.c:2693
 filename_mountpoint+0x190/0x3c0 /fs/namei.c:2715
 user_path_mountpoint_at+0x3a/0x50 /fs/namei.c:2745
 ksys_umount+0x167/0xf00 /fs/namespace.c:1680
 __do_sys_umount /fs/namespace.c:1706 [inline]
 __se_sys_umount /fs/namespace.c:1704 [inline]
 __x64_sys_umount+0x54/0x80 /fs/namespace.c:1704
 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c257
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:00007ffc5a5ade48 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00000000001a2987 RCX: 000000000045c257
RDX: 0000000000403520 RSI: 0000000000000002 RDI: 00007ffc5a5adef0
RBP: 00000000000005bd R08: 0000000000000000 R09: 0000000000000010
R10: 000000000000000a R11: 0000000000000202 R12: 00007ffc5a5aef80
R13: 0000555556744940 R14: 0000000000000000 R15: 00007ffc5a5aef80