rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=b61c/1/0x4000000000000000 softirq=18011/18011 fqs=0
rcu: 	(detected by 1, t=10505 jiffies, g=11433, q=296 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6476 Comm: syz.1.135 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:do_raw_spin_lock+0x125/0x290
Code: 00 00 c7 44 24 40 00 00 00 00 48 89 df be 04 00 00 00 e8 ce d0 85 00 48 8d 7c 24 40 be 04 00 00 00 e8 bf d0 85 00 8b 44 24 40 <b9> 01 00 00 00 f0 0f b1 0b 0f 85 dd 00 00 00 65 8b 1d 29 c7 02 11
RSP: 0018:ffffc900000077c0 EFLAGS: 00000097
RAX: 0000000000000000 RBX: ffff88804b027a80 RCX: ffffffff819e18f1
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90000007800
RBP: ffffc90000007870 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f00 R12: ffff88804b027a90
R13: ffff88804b027a88 R14: 1ffff11009604f52 R15: 1ffff11009604f51
FS:  00007f29e9e606c0(0000) GS:ffff8880b8612000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c34a07e CR3: 000000010d93c000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 _raw_spin_lock_irqsave+0xb3/0xf0
 hrtimer_try_to_cancel+0x22b/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+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110
Code: 74 05 e8 6b d0 49 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 23 75 12 f6 65 8b 05 6c 41 23 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc90002f6faa0 EFLAGS: 00000206
RAX: e8c32ee9053bfb00 RBX: 0000000000000a02 RCX: e8c32ee9053bfb00
RDX: 0000000000000000 RSI: ffffffff8d9baed8 RDI: 0000000000000001
RBP: ffffc90002f6fb28 R08: ffffffff8fa3b537 R09: 1ffffffff1f476a6
R10: dffffc0000000000 R11: fffffbfff1f476a7 R12: dffffc0000000000
R13: 1ffff11020fa139b R14: ffff888107d0a6d0 R15: 1ffff920005edf54
 try_to_wake_up+0x7b7/0x12b0
 wake_up_q+0x85/0xd0
 futex_wake+0x4a0/0x560
 do_futex+0x395/0x420
 __se_sys_futex+0x36f/0x400
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f29e8f8ec29
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:00007f29e9e600e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f29e91d5fa8 RCX: 00007f29e8f8ec29
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f29e91d5fac
RBP: 00007f29e91d5fa0 R08: 7fffffffffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f29e91d6038 R14: 00007fff4e2c8300 R15: 00007fff4e2c83e8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g11433 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=4737
rcu: rcu_preempt kthread starved for 10505 jiffies! g11433 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27224 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>
