INFO: rcu detected stall in sys

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	INFO: rcu detected stall in sys_newfstat kernel				1	1616d	1616d	0/26	closed as invalid on 2019/12/04 14:04
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10499 ticks this GP) idle=422/1/0x4000000000000002 softirq=11893/11893 fqs=42 
	(t=10500 jiffies g=6341 q=176)
rcu: rcu_preempt kthread starved for 10413 jiffies! g6341 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    28864    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 0
CPU: 0 PID: 8379 Comm: udevd Not tainted 5.5.0-rc5-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:1517 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641
 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:mod_memcg_page_state+0x16/0x190 include/linux/memcontrol.h:653
Code: 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 54 53 41 89 f6 48 89 fb e8 ba 27 2e 00 <48> 83 c3 38 48 89 d8 48 c1 e8 03 49 bc 00 00 00 00 00 fc ff df 42
RSP: 0018:ffffc90001ab7938 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffffffff814896c6 RBX: ffffea00023ecf00 RCX: ffff88808f5be240
RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea00023ecf00
RBP: ffffc90001ab7958 R08: 000000000003a728 R09: ffffed1012d5a731
R10: ffffed1012d5a731 R11: 0000000000000000 R12: ffff8880a4de3da0
R13: dffffc0000000000 R14: 00000000fffffffc R15: ffff888096ad3978
 free_thread_stack+0x168/0x590 kernel/fork.c:280
 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:tomoyo_check_acl+0x10b/0x3a0 security/tomoyo/domain.c:173
Code: 8d 5e 19 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 ea 00 00 00 0f b6 1b 48 8b 55 c8 48 89 d0 48 c1 e8 03 42 0f b6 04 38 <84> c0 0f 85 e9 00 00 00 44 0f b6 3a 0f b6 db 89 df 44 89 fe e8 fc
RSP: 0018:ffffc90001ab7bb8 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000
RDX: ffffc90001ab7cb8 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90001ab7c10 R08: ffffffff8360867d R09: ffffffff8360e728
R10: ffff88808f5be240 R11: 0000000000000003 R12: ffff88809a795d00
R13: ffff888094feb410 R14: ffff88809a795d00 R15: dffffc0000000000
 tomoyo_path_permission security/tomoyo/file.c:586 [inline]
 tomoyo_path_perm+0x53e/0x850 security/tomoyo/file.c:838
 tomoyo_inode_getattr+0x1c/0x20 security/tomoyo/tomoyo.c:129
 security_inode_getattr+0xd5/0x150 security/security.c:1222
 vfs_getattr+0x2a/0x6d0 fs/stat.c:115
 vfs_statx_fd fs/stat.c:145 [inline]
 vfs_fstat include/linux/fs.h:3265 [inline]
 __do_sys_newfstat fs/stat.c:378 [inline]
 __se_sys_newfstat fs/stat.c:375 [inline]
 __x64_sys_newfstat+0xa3/0x130 fs/stat.c:375
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fe0c027ccb4
Code: 00 f7 d8 64 89 02 83 c8 ff c3 90 90 90 90 90 90 90 90 90 90 90 90 83 ff 01 89 f0 77 19 48 63 f8 48 89 d6 b8 05 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 18 f3 c3 66 90 48 8b 05 51 51 2b 00 64 c7 00
RSP: 002b:00007ffcc532ccb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 0000000001514a00 RCX: 00007fe0c027ccb4
RDX: 00007ffcc532ccc0 RSI: 00007ffcc532ccc0 RDI: 0000000000000005
RBP: 0000000000003fff R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000a
R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffcc532d240