rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=48401, q=353 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294981682-4294971180), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g48401 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=18127
rcu: rcu_preempt kthread starved for 10502 jiffies! g48401 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:27160 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: 14354 Comm: syz.6.2533 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+0x295/0x3e0
Code: 5c 24 08 48 c7 c7 db a5 ba 8d e8 66 ab dd 09 b8 ff ff ff ff 65 0f c1 05 09 a9 03 11 83 f8 01 75 51 48 c7 44 24 20 00 00 00 00 <9c> 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74
RSP: 0018:ffffc900000073d8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000087 RCX: 357d0353ed7e1d00
RDX: 0000000000000000 RSI: ffffffff8dbaa5db RDI: ffffffff8be34480
RBP: ffff888041d9c470 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000e78 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88804b027a98 R15: ffff888041d9b980
FS:  00007f0e929886c0(0000) GS:ffff8880b8611000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e763fff CR3: 0000000029186000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000082
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+0x52/0xc0
 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:ffffc90000007c90 EFLAGS: 00000286
RAX: 357d0353ed7e1d00 RBX: ffff88804b025900 RCX: 357d0353ed7e1d00
RDX: 0000000000000000 RSI: ffffffff8d9baf27 RDI: 0000000000000001
RBP: ffffc90000007e10 R08: ffffffff8fa3b537 R09: 1ffffffff1f476a6
R10: dffffc0000000000 R11: fffffbfff1f476a7 R12: ffff88804b025900
R13: 1ffff92000000fac R14: ffffc90000137a80 R15: ffffc90000007d60
 __run_timer_base+0x60a/0x860
 run_timer_softirq+0xb7/0x180
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:get_unused_fd_flags+0x57/0x80
Code: 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 be c1 e6 ff 41 bf f0 03 00 00 4d 03 3e 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 <74> 08 4c 89 ff e8 9f c1 e6 ff 49 8b 37 31 ff 89 da 5b 41 5c 41 5e
RSP: 0018:ffffc90002d8fcd8 EFLAGS: 00000246
RAX: 1ffff11003ae7d9e RBX: 0000000000080002 RCX: ffff888041d9b980
RDX: 0000000000000000 RSI: 000000000000000a RDI: 0000000000080002
RBP: ffffc90002d8fee0 R08: ffff8881000120fb R09: 1ffff1102000241f
R10: dffffc0000000000 R11: ffffed1020002420 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff888041d9c2a0 R15: ffff88801d73ecf0
 __se_sys_perf_event_open+0x46b/0x1d70
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0e91b8ec29
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:00007f0e92988038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f0e91dd5fa0 RCX: 00007f0e91b8ec29
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000180
RBP: 00007f0e91c11e41 R08: 000000000000000a R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0e91dd6038 R14: 00007f0e91dd5fa0 R15: 00007ffeddd42908
 </TASK>
