rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=47353, q=204 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294985004-4294974502), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g47353 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=19089
rcu: rcu_preempt kthread starved for 10502 jiffies! g47353 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:26632 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: 14281 Comm: syz.0.2459 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+0x0/0x120
Code: c7 20 3e e3 8b 48 c7 c6 60 3e e3 8b eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 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 5e 26 07 48 89 44 24
RSP: 0018:ffffc900001e0810 EFLAGS: 00000046
RAX: ffffffffffffffff RBX: 0000000000000087 RCX: 4c9e0451000b0500
RDX: 0000000000000000 RSI: ffffffff8dba9863 RDI: ffffffff8be33e80
RBP: ffff888020c4e130 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200003c100 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888136627a98 R15: ffff888020c4d640
FS:  00007f9a938246c0(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32a1aff8 CR3: 000000010e15c000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 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:do_syscall_64+0xc3/0x3b0
Code: 00 48 8b 7d 08 48 89 7b 18 e8 09 5a 00 00 0f 1f 44 00 00 0f 1f 44 00 00 90 e8 39 6b 4d f6 90 90 e8 e2 6a 4d f6 fb 49 8b 57 08 <f6> c2 3f 74 0e 4c 89 f7 4c 89 ee e8 fd 5d 30 f6 49 89 c4 90 90 41
RSP: 0018:ffffc90006857ef0 EFLAGS: 00000286
RAX: 4c9e0451000b0500 RBX: ffffc90006857ef0 RCX: 4c9e0451000b0500
RDX: 0000000000000000 RSI: ffffffff8d9ba191 RDI: ffffffff8be33e80
RBP: ffffc90006857f48 R08: ffffffff8fa3a937 R09: 1ffffffff1f47526
R10: dffffc0000000000 R11: fffffbfff1f47527 R12: 0000000000000101
R13: 0000000000000101 R14: ffffc90006857f58 R15: ffff888020c4d640
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9a9298eba9
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:00007f9a93824038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9a92bd5fa0 RCX: 00007f9a9298eba9
RDX: 6b465dd4c7b27d96 RSI: 0000200000000240 RDI: ffffffffffffff9c
RBP: 00007f9a92a11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9a92bd6038 R14: 00007f9a92bd5fa0 R15: 00007ffd811a2d58
 </TASK>
