rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=30337, q=294 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294970298-4294959796), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g30337 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=13146
rcu: rcu_preempt kthread starved for 10502 jiffies! g30337 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 ->cpu=0
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:26728 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 10793 Comm: syz.0.1482 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:_raw_spin_lock_irqsave+0x6e/0xf0
Code: 49 c1 ef 03 48 b8 f1 f1 f1 f1 00 f3 f3 f3 49 bc 00 00 00 00 00 fc ff df 4b 89 04 27 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 <4c> 8b 74 24 20 fa 41 f7 c6 00 02 00 00 74 05 e8 de c4 49 f6 bf 01
RSP: 0018:ffffc90000007880 EFLAGS: 00000802
RAX: f3f3f300f1f1f1f1 RBX: ffff88804b027a80 RCX: ffff888048e61cc0
RDX: 0000000000010000 RSI: 0000000000000000 RDI: ffff88804b027a80
RBP: ffffc90000007918 R08: ffff88804b027a83 R09: 1ffff11009604f50
R10: dffffc0000000000 R11: ffffed1009604f51 R12: dffffc0000000000
R13: ffff88804b027b00 R14: dffffc0000000000 R15: 1ffff92000000f10
FS:  00007ff9d60af6c0(0000) GS:ffff8880b8611000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31f15ff8 CR3: 0000000028308000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 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:_raw_spin_unlock_irq+0x29/0x50
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 5a d5 1f f6 48 89 df e8 b2 6c 20 f6 e8 ad bf 49 f6 fb bf 01 00 00 00 <e8> 82 64 12 f6 65 8b 05 cb 40 23 07 85 c0 74 07 5b c3 cc cc cc cc
RSP: 0018:ffffc900085a7bb8 EFLAGS: 00000286
RAX: b91a9bc13c1cdf00 RBX: ffff888114a53800 RCX: b91a9bc13c1cdf00
RDX: 0000000000000006 RSI: ffffffff8d9baf27 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffff8fa3b537 R09: 1ffffffff1f476a6
R10: dffffc0000000000 R11: fffffbfff1f476a7 R12: ffff888038a21368
R13: dffffc0000000000 R14: ffff888114a53800 R15: 1ffff1100714426d
 _perf_event_refresh+0x107/0x250
 perf_ioctl+0x5e5/0x1ec0
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff9d518ec29
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:00007ff9d60af038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ff9d53d5fa0 RCX: 00007ff9d518ec29
RDX: 0000000000000003 RSI: 0000000000002402 RDI: 000000000000000b
RBP: 00007ff9d5211e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff9d53d6038 R14: 00007ff9d53d5fa0 R15: 00007ffe302e2d08
 </TASK>
