rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=a3a/1/0x4000000000000002 softirq=11698/11698 fqs=39 
	(t=10501 jiffies g=6053 q=78)
rcu: rcu_preempt kthread starved for 10424 jiffies! g6053 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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 1
CPU: 1 PID: 8073 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:__memcg_kmem_uncharge+0x211/0x2e0 mm/memcontrol.c:2925
Code: 65 db a4 ff 48 c7 c7 98 4b 0d 89 e8 59 97 00 00 bf 01 00 00 00 e8 2f e3 9b ff 65 8b 05 d4 fd 4a 7e 85 c0 74 53 48 83 c4 08 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 49 8d 5f 10 48 89 df be 08 00 00 00
RSP: 0018:ffffc90001cb74e8 EFLAGS: 00000292 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: ffffea00028b0a00 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea00028b0a00
RBP: ffffc90001cb7508 R08: dffffc0000000000 R09: fffffbfff120248a
R10: fffffbfff120248a R11: 0000000000000000 R12: ffffea00028b0a00
R13: 1ffffd4000516147 R14: ffffea00028b0a38 R15: 0000000000000000
 memcg_kmem_uncharge include/linux/memcontrol.h:1402 [inline]
 free_thread_stack+0x12e/0x590 kernel/fork.c:284
 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+0x50/0x280 security/tomoyo/util.c:918
Code: 4c 89 e0 48 c1 e8 03 42 80 3c 28 00 74 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
RSP: 0018:ffffc90001cb7768 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff02
RAX: 1ffff110126f20e3 RBX: 1ffff11013df6394 RCX: ffff888090a24340
RDX: 0000000000000000 RSI: ffff888093790718 RDI: ffffc90001cb78d0
RBP: ffffc90001cb77a8 R08: ffffffff835564ea R09: ffffffff83569c8c
R10: ffff888090a24340 R11: 0000000000000002 R12: ffffc90001cb78d0
R13: dffffc0000000000 R14: ffff88809efb1ca0 R15: ffff888093790718
 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_check_open_permission+0x3ce/0x9d0 security/tomoyo/file.c:777
 tomoyo_file_open+0x141/0x190 security/tomoyo/tomoyo.c:319
 security_file_open+0x65/0x2f0 security/security.c:1497
 do_dentry_open+0x351/0x10c0 fs/open.c:784
 vfs_open+0x73/0x80 fs/open.c:914
 do_last fs/namei.c:3412 [inline]
 path_openat+0x1397/0x44a0 fs/namei.c:3529
 do_filp_open+0x192/0x3d0 fs/namei.c:3559
 do_sys_open+0x29f/0x560 fs/open.c:1097
 __do_sys_open fs/open.c:1115 [inline]
 __se_sys_open fs/open.c:1110 [inline]
 __x64_sys_open+0x87/0x90 fs/open.c:1110
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f3d893b2120
Code: 48 8b 15 1b 4d 2b 00 f7 d8 64 89 02 83 c8 ff c3 90 90 90 90 90 90 90 90 90 90 83 3d d5 a4 2b 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 5e 8c 01 00 48 89 04 24
RSP: 002b:00007ffedb8e4fb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3d893b2120
RDX: 0000000000000124 RSI: 0000000000080000 RDI: 00007ffedb8e5060
RBP: 0000000001585744 R08: 0000000001585744 R09: 00007f3d89407c20
R10: 7269762f73656369 R11: 0000000000000246 R12: 00000000015846d0
R13: 00000000015847c0 R14: 000000000156b250 R15: 0000000001570e10