rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=9064/1/0x4000000000000000 softirq=20929/20929 fqs=0
rcu: 	(detected by 0, t=10506 jiffies, g=14985, q=197 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7356 Comm: syz.1.416 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:hrtimer_try_to_cancel+0xba/0x420
Code: 01 31 ff e8 a8 1f 12 00 89 e8 83 e0 01 0f 85 02 01 00 00 e8 58 1b 12 00 48 8b 44 24 28 42 0f b6 04 30 84 c0 0f 85 ac 00 00 00 <48> 8b 04 24 44 0f b6 28 31 ff 44 89 ee e8 34 1e 12 00 45 85 ed 0f
RSP: 0000:ffffc90007067868 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888136627b10 RCX: ffff888032ef1cc0
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00000000002774a2 R08: ffff888136627a83 R09: 1ffff11026cc4f50
R10: dffffc0000000000 R11: ffffed1026cc4f51 R12: 1ffff11026cc4f62
R13: dffffc0000000000 R14: dffffc0000000000 R15: ffff888136627b00
FS:  00007fccd5bcb6c0(0000) GS:ffff8881a3c11000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fccd5bcafc8 CR3: 0000000031916000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 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: 0033:0x7fccd4d8ec31
Code: 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 83 c8 ff c3 66 2e 0f 1f
RSP: 002b:00007fccd5bcb0e8 EFLAGS: 00000217
RAX: 0000000000000000 RBX: 00007fccd4fd5fa8 RCX: 00007fccd4d8ec29
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fccd4fd5fa8
RBP: 00007fccd4fd5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fccd4fd6038 R14: 00007ffc5c7bbf30 R15: 00007ffc5c7bc018
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g14985 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=8347
rcu: rcu_preempt kthread starved for 10506 jiffies! g14985 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>
