rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=dc9c/1/0x4000000000000000 softirq=17718/17718 fqs=0
rcu: 	(detected by 1, t=10505 jiffies, g=11601, q=511 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6504 Comm: syz.2.174 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_release+0x70/0x3e0
Code: e8 45 f1 08 00 84 c0 75 0d f6 05 79 14 f0 0d 01 0f 84 ad 02 00 00 83 3d 5d 61 06 0e 00 0f 84 44 02 00 00 65 8b 05 20 9b 03 11 <85> c0 0f 85 35 02 00 00 65 4c 8b 3c 25 08 e0 a0 92 41 83 bf ec 0a
RSP: 0018:ffffc90000007818 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 0000000000000802 RCX: e6708882e19dae00
RDX: 0000000000010000 RSI: ffffffff8be343e0 RDI: ffffffff8be343a0
RBP: ffffc90000007918 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f00 R12: dffffc0000000000
R13: ffffffff81adad5e R14: ffff88804b027a98 R15: 1ffff92000000f10
FS:  00007f8cf40cc6c0(0000) GS:ffff8880b8612000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c35e8de CR3: 0000000028c44000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 _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:perf_trace_init+0x96/0x2d0
Code: 5a 00 48 8b 1d 7b 9b 50 0c 48 81 fb 60 d7 19 8e 0f 84 75 01 00 00 4c 89 24 24 4c 8d 63 30 4c 89 e0 48 c1 e8 03 42 0f b6 04 30 <84> c0 0f 85 17 01 00 00 4d 63 24 24 4c 89 ff 4c 89 e6 e8 e3 8b f6
RSP: 0018:ffffc900071f7a78 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: ffffffff8f4e9380 RCX: 0000000000080000
RDX: ffffc90004189000 RSI: 000000000000071a RDI: 000000000000071b
RBP: 0000000000000002 R08: ffffffff8fa3b537 R09: 1ffffffff1f476a6
R10: dffffc0000000000 R11: fffffbfff1f476a7 R12: ffffffff8f4e93b0
R13: 0000000000000000 R14: dffffc0000000000 R15: 000000000000014a
 perf_tp_event_init+0x8d/0x120
 perf_try_init_event+0x17f/0x870
 perf_event_alloc+0x133e/0x2be0
 __se_sys_perf_event_open+0x772/0x1d70
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8cf318ec29
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:00007f8cf40cc038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f8cf33d5fa0 RCX: 00007f8cf318ec29
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000180
RBP: 00007f8cf3211e41 R08: 000000000000000a R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8cf33d6038 R14: 00007f8cf33d5fa0 R15: 00007ffe60cbdf88
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g11601 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=5455
rcu: rcu_preempt kthread starved for 10505 jiffies! g11601 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27224 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>
