rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10506 jiffies, g=30677, q=60 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10506 (4294968659-4294958153), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g30677 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=13380
rcu: rcu_preempt kthread starved for 10506 jiffies! g30677 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:26632 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: 9976 Comm: syz.2.1121 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:lock_acquire+0x185/0x360
Code: 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 7b 41 03 11 48 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b <41> 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 65 8b 05 65 81 03 11
RSP: 0018:ffffc90000007848 EFLAGS: 00000082
RAX: 66d10cb8c4d7c800 RBX: ffff88804b027a80 RCX: 66d10cb8c4d7c800
RDX: 0000000000000000 RSI: ffffffff8dba91a8 RDI: ffffffff8be33c00
RBP: ffffffff81ada58b R08: 0000000000000000 R09: ffffffff81ada58b
R10: dffffc0000000000 R11: ffffed1009604f51 R12: 0000000000000000
R13: ffff88804b027a98 R14: 0000000000000001 R15: 0000000000000046
FS:  00007fc071e276c0(0000) GS:ffff8880b8615000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc071e05fc8 CR3: 00000000285de000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 _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:do_syscall_64+0xc3/0x3b0
Code: 00 48 8b 7d 08 48 89 7b 18 e8 09 5a 00 00 0f 1f 44 00 00 0f 1f 44 00 00 90 e8 d9 88 4d f6 90 90 e8 82 88 4d f6 fb 49 8b 57 08 <f6> c2 3f 74 0e 4c 89 f7 4c 89 ee e8 fd 7b 30 f6 49 89 c4 90 90 41
RSP: 0018:ffffc90002c1fef0 EFLAGS: 00000286
RAX: 66d10cb8c4d7c800 RBX: ffffc90002c1fef0 RCX: 66d10cb8c4d7c800
RDX: 0000000000000000 RSI: ffffffff8d9b9cae RDI: ffffffff8be33c00
RBP: ffffc90002c1ff48 R08: ffffffff8fa3a637 R09: 1ffffffff1f474c6
R10: dffffc0000000000 R11: fffffbfff1f474c7 R12: 00000000000000ca
R13: 00000000000000ca R14: ffffc90002c1ff58 R15: ffff8881087a3980
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc070f8ec29
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:00007fc071e270e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007fc0711d5fa8 RCX: 00007fc070f8ec29
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc0711d5fa8
RBP: 00007fc0711d5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc0711d6038 R14: 00007ffdf0470cc0 R15: 00007ffdf0470da8
 </TASK>
