rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=5abc/1/0x4000000000000000 softirq=61203/61203 fqs=0
rcu: 	(detected by 1, t=10502 jiffies, g=47785, q=444 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13343 Comm: syz.2.1654 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:hrtimer_cancel+0x33/0x50
Code: e8 a2 28 12 00 48 89 df e8 9a f9 ff ff 89 c5 31 ff 89 c6 e8 cf 2c 12 00 85 ed 78 0c e8 86 28 12 00 eb 1a e8 7f 28 12 00 f3 90 <48> 89 df e8 75 f9 ff ff 85 c0 78 ed 89 c5 e8 6a 28 12 00 89 e8 5b
RSP: 0018:ffffc90000007990 EFLAGS: 00000006
RAX: ffffffff81ac4d61 RBX: ffff88803eb671e8 RCX: ffff888021493a00
RDX: 0000000000010000 RSI: 0000000000000004 RDI: 00000000ffffffff
RBP: 00000000ffffffff R08: ffff88804b227ac3 R09: 1ffff11009644f58
R10: dffffc0000000000 R11: ffffed1009644f59 R12: ffff88803eb67290
R13: dffffc0000000000 R14: ffff88803eb671e8 R15: ffffffffffff3f4b
FS:  00007f367f3676c0(0000) GS:ffff8880b8d73000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f367c7d5d58 CR3: 00000000273d4000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 cpu_clock_event_stop+0xd9/0x130
 __perf_event_overflow+0x580/0xe40
 perf_swevent_hrtimer+0x3b8/0x500
 __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+0x0/0x90
Code: 7c 11 10 48 89 74 11 18 48 89 44 11 20 e9 98 d3 7b 09 cc 0f 1f 80 00 00 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 4a 92 65 8b 0d f8 55
RSP: 0018:ffffc900036bfa90 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffff888021493a00 RCX: ffff888021493a00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8182d192
R10: dffffc0000000000 R11: fffffbfff1eb9aa7 R12: dffffc0000000000
R13: 0000000000000b00 R14: ffff888021494350 R15: 0000000000000000
 exit_signals+0x7d/0x600
 do_exit+0x352/0x2300
 do_group_exit+0x21c/0x2d0
 get_signal+0x1285/0x1340
 arch_do_signal_or_restart+0xa0/0x790
 exit_to_user_mode_loop+0x72/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f367e58ec29
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:00007f367f367038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f367e7d5fa0 RCX: 00007f367e58ec29
RDX: 0000000000000005 RSI: 0000000000002402 RDI: 0000000000000007
RBP: 00007f367e611e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f367e7d6038 R14: 00007f367e7d5fa0 R15: 00007ffdc6206d98
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g47785 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=19824
rcu: rcu_preempt kthread starved for 10502 jiffies! g47785 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:27256 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
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>
