rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=eecc/1/0x4000000000000000 softirq=23992/23992 fqs=0
rcu: 	(detected by 1, t=10502 jiffies, g=13701, q=1704 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7497 Comm: dhcpcd 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+0x120/0x360
Code: 41 f7 c7 00 02 00 00 41 0f 94 c1 4c 89 ef 89 de 8b 54 24 04 44 89 e1 45 89 f0 6a 00 6a 00 6a 00 55 ff 74 24 30 e8 e0 02 00 00 <48> 83 c4 28 48 c7 c7 e9 5f ba 8d e8 e0 36 dc 09 b8 ff ff ff ff 65
RSP: 0000:ffffc90000007b38 EFLAGS: 00000086
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 7d6ccf3a31716900
RDX: 0000000000000000 RSI: ffff88803e36e1d0 RDI: ffff88803e36d640
RBP: ffffffff84d0420a R08: 0000000000000000 R09: ffffffff84d0420a
R10: ffffc90000007cb0 R11: fffff52000000f98 R12: 0000000000000000
R13: ffffffff99d68bd0 R14: 0000000000000001 R15: 0000000000000046
FS:  00007f4185c21740(0000) GS:ffff8880b861b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005620358bd7a8 CR3: 00000000117f2000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 _raw_spin_lock_irqsave+0xa7/0xf0
 debug_object_deactivate+0x9a/0x250
 debug_deactivate+0x1d/0x200
 __hrtimer_run_queues+0x2b0/0xc60
 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_cmp8+0x37/0x90
Code: 08 50 a0 92 65 8b 15 28 a2 e0 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 3c 16 00 00 00 74 4e 8b 91 18 16 00 00 <83> fa 03 75 43 48 8b 91 20 16 00 00 44 8b 89 1c 16 00 00 49 c1 e1
RSP: 0000:ffffc900026cfa38 EFLAGS: 00000246
RAX: ffffffff820a8405 RBX: ffffc900026cfd38 RCX: ffff88803e36d640
RDX: 0000000000000000 RSI: 8000000000000025 RDI: 8000000000000025
RBP: ffffc900026cfbf0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520004d9f28 R12: ffffea0000000000
R13: 0000000000000001 R14: 8000000000000025 R15: 8000000000000025
 do_wp_page+0x1a75/0x5800
 __handle_mm_fault+0x1033/0x5440
 handle_mm_fault+0x40a/0x8e0
 do_user_addr_fault+0xa81/0x1390
 exc_page_fault+0x76/0xf0
 asm_exc_page_fault+0x26/0x30
RIP: 0033:0x7f4185c9d6df
Code: 4c 2c 08 01 48 39 cd 74 7e 49 83 4c 24 08 04 eb 76 48 8b 55 70 49 8d 04 1c 48 8d 3d 55 d8 0e 00 4c 3b 72 18 0f 85 51 f8 ff ff <4c> 89 70 18 48 89 50 10 48 89 45 70 48 89 42 18 48 81 fb ff 03 00
RSP: 002b:00007fff50427ff0 EFLAGS: 00010246
RAX: 00005620358bd790 RBX: 0000000000002010 RCX: 00007f4185dc6aa0
RDX: 00007f4185dc6b00 RSI: 0000000002030000 RDI: 00007f4185d8af2a
RBP: 00007f4185dc6aa0 R08: 00007f4185dc6b30 R09: 0000000000000010
R10: 000000000000020f R11: 0000000000000000 R12: 00005620358bb780
R13: 0000000000002e60 R14: 00007f4185dc6b00 R15: 0000000000000e50
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g13701 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=4116
rcu: rcu_preempt kthread starved for 10502 jiffies! g13701 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27160 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+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
