rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=20781, q=391 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294962189-4294951687), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g20781 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=9178
rcu: rcu_preempt kthread starved for 10502 jiffies! g20781 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: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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8805 Comm: syz.0.798 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:debug_smp_processor_id+0x0/0x20
Code: c7 40 38 1f 8e 4c 89 f6 e8 ad 67 85 f9 e9 66 ff ff ff cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 c7 c7 a0 3b e3 8b 48 c7 c6 e0 3b e3 8b eb 1c 66 66
RSP: 0018:ffffc900000077f0 EFLAGS: 00000083
RAX: 0000000000000000 RBX: 0000000000000802 RCX: ffff888105e21cc0
RDX: 0000000000010000 RSI: ffffffff81ada71e RDI: ffff88804b027a98
RBP: ffffc90000007918 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f00 R12: dffffc0000000000
R13: ffffffff81ada71e R14: ffff88804b027a98 R15: 1ffff92000000f10
FS:  00007f02f15526c0(0000) GS:ffff8880b8615000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555929ba808 CR3: 000000011f9e4000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000082
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 rcu_is_watching+0x15/0xb0
 lock_release+0x4b/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:__sanitizer_cov_trace_pc+0x4/0x70
Code: 00 00 00 48 8b 3d f4 65 fe 0b 48 89 de 5b e9 23 a1 58 00 cc cc cc 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 0c 25 08 b0 a0 92 65 8b 15 18 f1 e0 10 81 e2
RSP: 0018:ffffc9000425fdc8 EFLAGS: 00000286
RAX: ffff8881137fb6c0 RBX: ffff88801d2e2a28 RCX: 0000000000080000
RDX: ffffc90008e9a000 RSI: 0000000000000084 RDI: 0000000000000085
RBP: ffff8881137fb6c0 R08: 00000000ffffffff R09: 0000000000000000
R10: ffff88811e59a9a0 R11: ffffffff81ac4b00 R12: dffffc0000000000
R13: ffff8881137fb6c0 R14: 0000000000000010 R15: 0000000000000002
 get_next_ino+0x11/0x1a0
 __sock_create+0x145/0x9f0
 __sys_socket+0xd7/0x1b0
 __x64_sys_socket+0x7a/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f02f078ec29
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:00007f02f1552038 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00007f02f09d6090 RCX: 00007f02f078ec29
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000010
RBP: 00007f02f0811e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f02f09d6128 R14: 00007f02f09d6090 R15: 00007ffd25d6e548
 </TASK>
