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 (2) kernel				1	1562d	1562d	0/26	closed as invalid on 2020/01/08 05:33
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (1 GPs behind) idle=61e/1/0x4000000000000002 softirq=11256/11258 fqs=32 
	(t=10500 jiffies g=6989 q=217)
rcu: rcu_preempt kthread starved for 10433 jiffies! g6989 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29032    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: 4165 Comm: udevd 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:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:98
Code: 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 53 48 89 fb e8 13 00 00 00 48 8b 3d 74 25 cd 07 48 89 de e8 64 02 3b 00 5b 5d c3 cc <48> 8b 04 24 65 48 8b 0c 25 c0 1d 02 00 65 8b 15 b8 81 8b 7e f7 c2
RSP: 0018:ffffc90001dc78e0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffff1101188f921 RBX: ffffea00028d5dc0 RCX: ffff8880a004a500
RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea00028d5dc0
RBP: ffffc90001dc7920 R08: dffffc0000000000 R09: fffffbfff120248a
R10: fffffbfff120248a R11: 0000000000000000 R12: ffff88808c47c9a0
R13: dffffc0000000000 R14: 1ffff1101188f934 R15: ffff8880a92dba28
 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_path_matches_pattern+0x5d/0x280 security/tomoyo/util.c:918
Code: 08 4c 89 e7 e8 34 73 5b fe 49 8b 04 24 48 89 45 c8 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 16 73 5b fe 49 8b 07 <48> 89 45 d0 49 8d 7f 0c 48 89 f8 48 c1 e8 03 42 8a 04 28 84 c0 0f
RSP: 0018:ffffc90001dc7b30 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff02
RAX: ffff888094f21da8 RBX: 1ffff11014023e84 RCX: ffff8880a004a500
RDX: 0000000000000000 RSI: ffff888094f21d98 RDI: ffffc90001dc7c60
RBP: ffffc90001dc7b70 R08: ffffffff835564ea R09: ffffffff83557a68
R10: ffff8880a004a500 R11: 0000000000000003 R12: ffffc90001dc7c60
R13: dffffc0000000000 R14: ffff8880a011f420 R15: ffff888094f21d98
 tomoyo_compare_name_union security/tomoyo/file.c:87 [inline]
 tomoyo_check_path_acl+0xf2/0x180 security/tomoyo/file.c:260
 tomoyo_check_acl+0x133/0x3a0 security/tomoyo/domain.c:172
 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: 0033:0x7f7ae06a5cb4
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:00007fff4e435b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 0000000001da5930 RCX: 00007f7ae06a5cb4
RDX: 00007fff4e435b30 RSI: 00007fff4e435b30 RDI: 0000000000000005
RBP: 00000000ffffffff R08: 00007f7ae0f9e7a0 R09: 00007f7ae0f9e7a0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000420724
R13: 0000000000000002 R14: 0000000000420724 R15: 0000000000420724