rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=16533, q=192 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294961710-4294951208), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g16533 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=6262
rcu: rcu_preempt kthread starved for 10502 jiffies! g16533 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: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>
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: 8116 Comm: syz.0.657 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+0x35/0x120
Code: 48 8b 05 be 4e 26 07 48 89 44 24 08 65 8b 05 c6 4e 26 07 65 8b 0d bb 4e 26 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d 9b 4e 26 07 <48> 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d e9
RSP: 0018:ffffc900001e0788 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0441a30ab5bc3400
RDX: 0000000000000000 RSI: ffffffff8be33e60 RDI: ffffffff8be33e20
RBP: ffffffff81ada78b R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1026cc4f51 R12: 0000000000000000
R13: ffff888136627a98 R14: 0000000000000000 R15: 0000000000000001
FS:  00007fc22b5896c0(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2809c1 CR3: 0000000032242000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_is_watching+0x15/0xb0
 lock_acquire+0x5f/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:__sanitizer_cov_trace_const_cmp4+0x18/0x90
Code: 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 14 25 08 d0 a0 92 65 8b 0d 78 0a e1 10 <81> e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 3c 16 00 00
RSP: 0018:ffffc900075078f0 EFLAGS: 00000246
RAX: ffffffff81b2f378 RBX: 00000000ffffffff RCX: 0000000080000000
RDX: ffff8881093dd640 RSI: 00000000ffffffff RDI: 00000000ffffffff
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff81b2f090
R10: 0000000000000000 R11: 00000000ffffffff R12: dffffc0000000000
R13: ffffc90007507aa0 R14: 0000000000000000 R15: ffffc90007507ae8
 __futex_hash+0x48/0x760
 futex_hash+0xe5/0x2d0
 futex_wait_setup+0xc9/0x590
 __futex_wait+0x148/0x3e0
 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: 0033:0x7fc22a78eba9
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:00007fc22b5890e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007fc22a9d5fa8 RCX: 00007fc22a78eba9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc22a9d5fa8
RBP: 00007fc22a9d5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc22a9d6038 R14: 00007ffc9b2eeab0 R15: 00007ffc9b2eeb98
 </TASK>
