rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=7c7c/1/0x4000000000000000 softirq=35519/35519 fqs=0
rcu: 	(detected by 0, t=10502 jiffies, g=30065, q=245 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 10150 Comm: syz.4.1231 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:mark_lock+0x3/0x190
Code: 8b 2c 24 e9 b0 fd ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 <41> 56 41 55 41 54 53 8b 46 20 89 c1 81 e1 00 00 03 00 83 f9 01 bb
RSP: 0018:ffffc900001e0738 EFLAGS: 00000046
RAX: 00000000000c4067 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffff888105b9c4c0 RDI: ffff888105b9b980
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81adabcb
R10: dffffc0000000000 R11: ffffed1026cc4f51 R12: 0000000000000002
R13: 0000000000000002 R14: ffff888105b9c4c0 R15: 0000000000000000
FS:  00007f94e53d86c0(0000) GS:ffff8881a3c11000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f94e5395fc8 CR3: 0000000106e2e000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __lock_acquire+0x65a/0xd20
 lock_acquire+0x120/0x360
 _raw_spin_lock_irqsave+0xa7/0xf0
 hrtimer_try_to_cancel+0x22b/0x420
 hrtimer_cancel+0x3b/0x50
 cpu_clock_event_stop+0xd9/0x130
 __perf_event_overflow+0x580/0xe40
 perf_swevent_hrtimer+0x3c5/0x550
 __hrtimer_run_queues+0x4e0/0xc60
 hrtimer_interrupt+0x45b/0xaa0
 __sysvec_apic_timer_interrupt+0x10b/0x410
 sysvec_apic_timer_interrupt+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:unwind_next_frame+0x37c/0x2390
Code: bd 00 00 00 00 00 fc ff df 0f 84 37 01 00 00 4c 8d 62 04 4c 8d 6a 05 4c 89 e0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 6d 19 00 00 <4c> 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 80 19 00 00 41 0f b6
RSP: 0018:ffffc90002a2f638 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff8fc0649c RCX: ffffffff8fc064a0
RDX: ffffffff9040db16 RSI: ffffffff9040db16 RDI: ffffffff8be34420
RBP: dffffc0000000000 R08: 000000000000000a R09: ffffffff8172d195
R10: ffffc90002a2f758 R11: ffffffff81ac5140 R12: ffffffff9040db1a
R13: ffffffff9040db1b R14: ffffc90002a2f708 R15: ffffffff8fc0649c
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_noprof+0x27a/0x4f0
 tomoyo_encode+0x28b/0x550
 tomoyo_realpath_from_path+0x58d/0x5d0
 tomoyo_path_number_perm+0x1e8/0x5a0
 security_file_ioctl+0xcb/0x2d0
 __se_sys_ioctl+0x47/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f94e458ec29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f94e53d8038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f94e47d5fa0 RCX: 00007f94e458ec29
RDX: 00002000000000c0 RSI: 00000000400454ca RDI: 0000000000000007
RBP: 00007f94e4611e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f94e47d6038 R14: 00007f94e47d5fa0 R15: 00007ffe374a96f8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g30065 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=12877
rcu: rcu_preempt kthread starved for 10502 jiffies! g30065 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:26664 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 rcu_gp_fqs_loop+0x301/0x1540
 rcu_gp_kthread+0x99/0x390
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
