rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10503 jiffies, g=9665, q=301 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10497 (4294956252-4294945755), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10496 jiffies! g9665 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=4331
rcu: rcu_preempt kthread starved for 10497 jiffies! g9665 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 ->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: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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6243 Comm: syz.2.99 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+0x3c7/0x420
Code: 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 7d 97 75 00 48 8b 3b 4c 89 fe e8 f2 54 cf 09 89 e8 48 83 c4 30 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 c7 17 12 00 31 ed eb e1
RSP: 0018:ffffc900001e0968 EFLAGS: 00000082
RAX: 00000000ffffffff RBX: ffff8880367607a8 RCX: 0000000000010000
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 00000000ffffffff
RBP: 00000000ffffffff R08: ffff888136627a83 R09: 1ffff11026cc4f50
R10: dffffc0000000000 R11: ffffed1026cc4f51 R12: ffff888036760850
R13: ffff888136627b00 R14: dffffc0000000000 R15: 0000000000000802
FS:  00007f53356a06c0(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f533567efc8 CR3: 000000011136a000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 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+0x195/0x2d0
Code: eb 1c e8 be 88 f6 ff eb 15 48 89 df e8 f4 bb 03 00 84 c0 0f 85 a1 00 00 00 e8 a7 88 f6 ff 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 21 08 5a 00 48 8b 1b 48 81 fb 20 d7 19 8e 74 45
RSP: 0018:ffffc9000457fa78 EFLAGS: 00000246
RAX: 1ffffffff1c88d3c RBX: ffffffff8e4469e0 RCX: ffff888109501cc0
RDX: 0000000000000000 RSI: 000000000000045e RDI: 000000000000014a
RBP: 0000000000000002 R08: ffffffff8fa3a937 R09: 1ffffffff1f47526
R10: dffffc0000000000 R11: fffffbfff1f47527 R12: 000000000000045e
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: 0033:0x7f533478eba9
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:00007f53356a0038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f53349d5fa0 RCX: 00007f533478eba9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000180
RBP: 00007f5334811e19 R08: 000000000000000a R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f53349d6038 R14: 00007f53349d5fa0 R15: 00007ffeab778e78
 </TASK>
