rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=508c/1/0x4000000000000000 softirq=51194/51194 fqs=0
rcu: 	(detected by 0, t=10505 jiffies, g=46381, q=305 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 11494 Comm: syz.1.1460 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+0x44/0x3e0
Code: 8b 05 50 60 03 11 48 89 44 24 28 0f 1f 44 00 00 65 8b 05 53 60 03 11 83 f8 08 0f 83 9a 02 00 00 89 c0 48 0f a3 05 3c 28 06 0e <73> 16 e8 45 f1 08 00 84 c0 75 0d f6 05 6b 0c f0 0d 01 0f 84 ad 02
RSP: 0000:ffffc90004b3f758 EFLAGS: 00000097
RAX: 0000000000000001 RBX: 0000000000000802 RCX: ffff8881068b1cc0
RDX: 0000000000010000 RSI: ffffffff81ada86e RDI: ffff888136627a98
RBP: ffffc90004b3f858 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000967ee8 R12: dffffc0000000000
R13: ffffffff81ada86e R14: ffff888136627a98 R15: 1ffff92000967ef8
FS:  00007fe7dfc586c0(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c326bfc CR3: 0000000027fa8000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 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: 0033:0x7fe7dec5e84f
Code: 20 e8 03 00 00 48 8d 3d 36 49 1b 00 48 89 d0 48 f7 64 24 28 31 c0 41 8b 36 48 c1 ea 12 48 01 ca 48 89 d9 48 2b 15 99 6e ea 00 <e8> 8c f9 fe ff 41 8b 76 2c 85 f6 7e 40 31 db 4c 8d 25 16 49 1b 00
RSP: 002b:00007fe7dfc58060 EFLAGS: 00000206
RAX: 0000000000000000 RBX: 00007fe7dedf8958 RCX: 00007fe7dedf8958
RDX: 0000000000010ab8 RSI: 0000000000000000 RDI: 00007fe7dee13167
RBP: 00007fe7defd5fa0 R08: 000000001b8470c9 R09: 7fffffffffffffff
R10: 3fffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe7defd6038 R14: 00007fe7defd5fa0 R15: 00007ffca7ca92d8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g46381 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=17954
rcu: rcu_preempt kthread starved for 10505 jiffies! g46381 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:26696 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>
