syzbot

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10500 ticks this GP) idle=622/1/0x4000000000000004 softirq=92706/92706 fqs=0 
	(t=10500 jiffies g=115681 q=5726)
rcu: rcu_preempt kthread starved for 10500 jiffies! g115681 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I29272    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x8e1/0x1f30 kernel/sched/core.c:4081
 schedule+0xdc/0x2b0 kernel/sched/core.c:4155
 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0x9b2/0x18d0 kernel/rcu/tree.c:1821
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 22831 Comm: syz-executor.1 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+0x197/0x210 lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x23b/0x28b 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:2827 [inline]
 rcu_sched_clock_irq.cold+0x509/0xc02 kernel/rcu/tree.c:2271
 update_process_times+0x2d/0x70 kernel/time/timer.c:1726
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167
 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1638
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x90/0xe0 kernel/locking/spinlock.c:191
Code: 48 c7 c0 58 34 53 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 39 48 83 3d ff 25 99 01 00 74 24 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 e1 67 96 f9 65 8b 05 12 10 48 78
RSP: 0018:ffff8880ae909a68 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff12a668b RBX: 0000000000000282 RCX: 0000000000000002
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000282
RBP: ffff8880ae909a78 R08: 1ffffffff15d29c5 R09: fffffbfff15d29c6
R10: fffffbfff15d29c5 R11: ffffffff8ae94e2f R12: ffff8880ae928300
R13: ffff8880ae928300 R14: ffff8880ae928300 R15: ffff8880ae928300
 __mod_timer kernel/time/timer.c:1057 [inline]
 mod_timer+0x507/0xc10 kernel/time/timer.c:1100
 sfq_perturbation+0x27e/0x1c80 net/sched/sch_sfq.c:620
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0xdca/0x1790 kernel/time/timer.c:1788
 __do_softirq+0x262/0x98c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x19b/0x1e0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1137
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:tomoyo_domain_quota_is_ok+0x131/0x540 security/tomoyo/util.c:1035
Code: 24 4c 3b 65 d0 0f 84 9c 00 00 00 e8 a9 5d 1f fe 49 8d 7c 24 18 48 ba 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 0f b6 04 10 <48> 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 69 03 00 00 41 0f b6 5c
RSP: 0018:ffff888021d578d0 EFLAGS: 00000a06 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: 0000000000000010 RCX: ffffc9000817a000
RDX: dffffc0000000000 RSI: ffffffff83558077 RDI: ffff8880914be198
RBP: ffff888021d57910 R08: ffff8880919e8400 R09: ffffed10043aaf2f
R10: ffffed10043aaf2e R11: 0000000000000000 R12: ffff8880914be180
R13: 0000000000000100 R14: 000000000000011e R15: 0000000000000000
 tomoyo_supervisor+0x2e8/0xef0 security/tomoyo/common.c:2087
 tomoyo_audit_path_number_log security/tomoyo/file.c:235 [inline]
 tomoyo_path_number_perm+0x42a/0x520 security/tomoyo/file.c:734
 tomoyo_path_mkdir+0xaa/0xf0 security/tomoyo/tomoyo.c:173
 security_path_mkdir+0x113/0x170 security/security.c:1029
 do_mkdirat+0x160/0x2a0 fs/namei.c:3828
 __do_sys_mkdir fs/namei.c:3846 [inline]
 __se_sys_mkdir fs/namei.c:3844 [inline]
 __x64_sys_mkdir+0x5c/0x80 fs/namei.c:3844
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45a679
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f1fad060c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 000000000045a679
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200002c0
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1fad0616d4
R13: 00000000004c0064 R14: 00000000004dd058 R15: 00000000ffffffff