rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10503 jiffies, g=20565, q=334 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10501 (4294960387-4294949886), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10500 jiffies! g20565 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=8015
rcu: rcu_preempt kthread starved for 10501 jiffies! g20565 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: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+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: 7464 Comm: syz.8.383 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+0x24/0xd20
Code: 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 48 83 ec 30 48 89 fb 65 48 8b 3c 25 08 e0 a0 92 45 31 ff 83 3d cc 6e 06 0e 00 <0f> 84 7e 0c 00 00 48 8b 03 48 3d 20 b3 64 93 0f 84 6f 0c 00 00 41
RSP: 0018:ffffc900001e0750 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffff888136627a98 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88810632d640
RBP: ffffffff81adabcb R08: 0000000000000001 R09: 0000000000000001
R10: dffffc0000000000 R11: ffffed1026cc4f51 R12: 0000000000000000
R13: ffff888136627a98 R14: 0000000000000001 R15: 0000000000000000
FS:  00007f643b6846c0(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33323ffc CR3: 0000000122c4e000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 lock_acquire+0x120/0x360
 _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_pc+0x5d/0x70
Code: 18 16 00 00 83 fa 02 75 21 48 8b 91 20 16 00 00 48 8b 32 48 8d 7e 01 8b 89 1c 16 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 <c3> cc cc cc cc cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90
RSP: 0018:ffffc9000294fd18 EFLAGS: 00000283
RAX: ffffffff81d08502 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc900034b1000 RSI: 0000000000000015 RDI: 0000000000000016
RBP: ffffc9000294feb8 R08: ffff88810632d640 R09: 0000000000000026
R10: 0000000000000025 R11: 0000000000000002 R12: 0000000000000005
R13: 000000000000002f R14: ffffc9000294fd60 R15: dffffc0000000000
 __sys_bpf+0x4f2/0x860
 __x64_sys_bpf+0x7c/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f643a78ec29
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:00007f643b684038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f643a9d5fa0 RCX: 00007f643a78ec29
RDX: 000000000000002f RSI: 0000200000000800 RDI: 0000000000000005
RBP: 00007f643a811e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f643a9d6038 R14: 00007f643a9d5fa0 R15: 00007ffe1f392e48
 </TASK>
