rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10504 jiffies, g=22741, q=286 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294964977-4294954475), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g22741 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=12085
rcu: rcu_preempt kthread starved for 10502 jiffies! g22741 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 ->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:R stack:27304 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9306 Comm: syz.0.963 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:check_preemption_disabled+0x1e/0x120
Code: 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 be ce 25 07 48 89 44 24 08 65 8b 05 c6 ce 25 07 <65> 8b 0d bb ce 25 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d 9b ce 25
RSP: 0018:ffffc900000077e0 EFLAGS: 00000082
RAX: 0000000000000000 RBX: 0000000000000087 RCX: 4345351f2aca8200
RDX: 0000000000000001 RSI: ffffffff8dbaa3f5 RDI: ffffffff8be34480
RBP: ffff8880217d4498 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f00 R12: 0000000000000001
R13: 0000000000000001 R14: ffff88804b027a98 R15: ffff8880217d3980
FS:  00007fb344f966c0(0000) GS:ffff8880b8612000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c366d35 CR3: 0000000011916000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 lock_release+0x27a/0x3e0
 _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+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:__futex_unqueue+0xbf/0x160
Code: 00 85 ed 74 2e 49 83 c7 18 4c 89 ff be ff ff ff ff e8 75 e2 c7 09 89 c5 31 ff 89 c6 e8 1a ad 0c 00 85 ed 74 6e e8 d1 a8 0c 00 <43> 80 3c 26 00 75 0e eb 14 e8 c3 a8 0c 00 43 80 3c 26 00 74 08 4c
RSP: 0018:ffffc90001dbfb70 EFLAGS: 00000287
RAX: ffffffff81b3188f RBX: ffffc90007287aa0 RCX: 0000000000080000
RDX: ffffc90007f79000 RSI: 00000000000003cb RDI: 00000000000003cc
RBP: 0000000000000001 R08: ffff888025f71ceb R09: 1ffff11004bee39d
R10: dffffc0000000000 R11: ffffed1004bee39e R12: dffffc0000000000
R13: ffffc90007287ad0 R14: 1ffff92000e50f5a R15: ffff888030c6a4e0
 futex_wake_mark+0xe2/0x200
 futex_wake+0x3bb/0x560
 do_futex+0x395/0x420
 __se_sys_futex+0x36f/0x400
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb34418ec29
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:00007fb344f960e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007fb3443d5fa8 RCX: 00007fb34418ec29
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fb3443d5fac
RBP: 00007fb3443d5fa0 R08: 7fffffffffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb3443d6038 R14: 00007ffcf3ee5730 R15: 00007ffcf3ee5818
 </TASK>
