rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=b40c/1/0x4000000000000000 softirq=61319/61319 fqs=0
rcu: 	(detected by 0, t=10506 jiffies, g=53793, q=170 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 15417 Comm: syz.8.2720 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+0x11c/0x3e0
Code: 8d 60 ff 49 8d af f0 0a 00 00 4d 63 ec 48 89 04 24 83 f8 32 0f 83 44 02 00 00 4a 8d 1c ad 00 00 00 00 4c 01 eb 48 8d 6c dd 00 <48> 89 ef 4c 89 f6 e8 89 4c dd 09 44 89 64 24 14 45 89 e5 85 c0 0f
RSP: 0000:ffffc90007947758 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: e97d435870757a00
RDX: 0000000000010000 RSI: ffffffff8d9ce553 RDI: ffffffff8be34280
RBP: ffff888036c7a7b0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000f28ee8 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888136627a98 R15: ffff888036c79cc0
FS:  00007ff38abf66c0(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2de22ff8 CR3: 000000010b962000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 _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: 0033:0x7ff38c85ea07
Code: ff ff 01 64 48 8b 04 25 00 00 00 00 48 8d b8 c8 fe ff ff e8 8b c1 0c 00 85 c0 0f 84 83 01 00 00 64 f0 83 2c 25 90 ff ff ff 01 <e8> d4 9b 0b 00 48 8b 0c 24 8b 00 48 83 b9 88 00 00 00 ff 89 81 90
RSP: 002b:00007ff38abf6060 EFLAGS: 00000246
RAX: 0000000000000004 RBX: 00007ff38cbd5fa0 RCX: 00007ff38ca11e41
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000010
RBP: 00007ff38ca11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff38cbd6038 R14: 00007ff38cbd5fa0 R15: 00007fffbc2f6648
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g53793 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=20963
rcu: rcu_preempt kthread starved for 10506 jiffies! g53793 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I 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>
