rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=33977, q=83 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294972619-4294962117), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g33977 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=13781
rcu: rcu_preempt kthread starved for 10502 jiffies! g33977 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 ->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:R stack:26896 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>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11860 Comm: syz.4.1794 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:check_preemption_disabled+0x40/0x120
Code: 08 65 8b 05 c6 fe 25 07 65 8b 0d bb fe 25 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d 9b fe 25 07 48 3b 4c 24 08 0f 85 cc 00 00 00 <48> 83 c4 10 5b 41 5e 41 5f 5d e9 81 ca 02 00 cc 48 c7 04 24 00 00
RSP: 0018:ffffc900001e0558 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ccbbf0a5551b9a00
RDX: ffff88801f45b980 RSI: ffffffff8be34260 RDI: ffffffff8be34220
RBP: ffffc900001e06b8 R08: ffffc900001e064f R09: 0000000000000000
R10: ffffc900001e0640 R11: fffff5200003c0ca R12: 0000000000000001
R13: ffffc900001e0640 R14: ffff88810e5e7080 R15: ffffffff8e009268
FS:  00007f5817e566c0(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5817e55fc8 CR3: 000000012bda8000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000200000000300
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_is_watching+0x15/0xb0
 rcu_read_lock_held+0x15/0x50
 trace_call_bpf+0x1f4/0x850
 perf_trace_run_bpf_submit+0x78/0x170
 perf_trace_lock+0x2f8/0x3b0
 lock_release+0x3b2/0x3e0
 _raw_spin_unlock_irqrestore+0x70/0x110
 hrtimer_try_to_cancel+0x3be/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:rcu_is_watching+0x6/0xb0
Code: e8 1f c9 59 03 eb cc 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 f3 0f 1e fa 41 57 <41> 56 53 65 ff 05 30 6e fa 10 e8 1b 6f d4 09 89 c3 83 f8 08 73 65
RSP: 0018:ffffc900091af688 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff9065fb01 RCX: ffff88801f45b980
RDX: ffffc900091af701 RSI: dffffc0000000000 RDI: ffffc900091af770
RBP: dffffc0000000000 R08: ffffc900091afea8 R09: 0000000000000000
R10: ffffc900091af7b8 R11: fffff52001235ef9 R12: ffffc900091afeb8
R13: ffffc900091a8000 R14: ffffc900091af768 R15: ffffffff8172d195
 unwind_next_frame+0x1965/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_noprof+0x27a/0x4f0
 tomoyo_realpath_from_path+0xe3/0x5d0
 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: 0033:0x7f5816f8ec29
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:00007f5817e56038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f58171d5fa0 RCX: 00007f5816f8ec29
RDX: 0000000000000006 RSI: 0000000000002402 RDI: 0000000000000003
RBP: 00007f5817011e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f58171d6038 R14: 00007f58171d5fa0 R15: 00007ffc8804dbd8
 </TASK>
