rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=5ff4/1/0x4000000000000000 softirq=45379/45379 fqs=0
rcu: 	(detected by 0, t=10502 jiffies, g=41705, q=154 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 12285 Comm: syz.4.1785 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_acquire+0x6c9/0xd20
Code: 08 00 00 00 e8 88 25 00 00 45 31 ff 85 c0 0f 84 f5 05 00 00 83 3d 36 a9 0e 18 00 75 13 48 63 44 24 20 48 0f a3 05 a7 19 0b 12 <0f> 83 15 05 00 00 31 ed 48 8b 3c 24 4c 8b bf e0 0a 00 00 48 83 7c
RSP: 0018:ffffc900001e0750 EFLAGS: 00000047
RAX: 0000000000000067 RBX: 0000000000000002 RCX: ffffffff9349e388
RDX: 0000000000000008 RSI: ffff8881111727b0 RDI: ffff888111171cc0
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81ada78b
R10: dffffc0000000000 R11: ffffed1026cc4f51 R12: ffffffffffffff02
R13: 0000000000000002 R14: ffff8881111727b0 R15: 0000000000000000
FS:  00007f4ce7c416c0(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001d80 CR3: 0000000029d28000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 lock_acquire+0x120/0x360
 _raw_spin_lock_irqsave+0xa7/0xf0
 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:trace_sched_exit_tp+0x2/0x110
Code: 55 fe ff ff 48 8b 7d b0 e8 fb 12 92 00 e9 47 fe ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 53 <66> 90 65 8b 05 59 a0 0f 11 83 f8 08 73 3b 89 c3 c1 e8 06 48 8d 3c
RSP: 0018:ffffc9000a0477a8 EFLAGS: 00000206
RAX: 0000000000000001 RBX: ffff8881000f8000 RCX: ffffffff8191299b
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffffc9000a0479d8 R08: ffff888020742b03 R09: 1ffff110040e8560
R10: dffffc0000000000 R11: ffffed10040e8561 R12: dffffc0000000000
R13: 1ffff11026cc7557 R14: ffff888111171cc0 R15: ffff8881000f9594
 __schedule+0x17ae/0x4cc0
 schedule+0x165/0x360
 __futex_wait+0x1c3/0x3e0
 futex_wait+0x104/0x360
 do_futex+0x333/0x420
 __se_sys_futex+0x36f/0x400
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4ce6d8eba9
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:00007f4ce7c410e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f4ce6fd5fa8 RCX: 00007f4ce6d8eba9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4ce6fd5fa8
RBP: 00007f4ce6fd5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4ce6fd6038 R14: 00007fffacd10ee0 R15: 00007fffacd10fc8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g41705 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=17057
rcu: rcu_preempt kthread starved for 10502 jiffies! g41705 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:26792 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>
