rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=22741, q=306 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294963606-4294953104), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g22741 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=10984
rcu: rcu_preempt kthread starved for 10502 jiffies! g22741 f0x2 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:26792 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: 8956 Comm: syz.3.807 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+0xa51/0xd20
Code: 90 0f 0b 90 90 90 31 c0 48 8b 3c 24 48 83 78 40 00 0f 84 8c 02 00 00 41 8b 46 20 25 ff 1f 00 00 48 0f a3 05 21 26 0b 12 73 10 <48> 69 c0 c8 00 00 00 48 8d 80 10 a3 49 93 eb 40 83 3d 88 b5 0e 18
RSP: 0018:ffffc90000006dd0 EFLAGS: 00000003
RAX: 0000000000000067 RBX: 0000000000000002 RCX: 0000000090213bdc
RDX: 00000000001a71fd RSI: 00000000727d5714 RDI: ffff88802412d640
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff81ada78b
R10: dffffc0000000000 R11: ffffed1009604f51 R12: 0000000000000068
R13: ffff88802412e130 R14: ffff88802412e180 R15: d6bf87c490213bdc
FS:  00007fdbf7b696c0(0000) GS:ffff8880b8612000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000010f846000 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+0x52/0xc0
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:unwind_next_frame+0x11a4/0x2390
Code: 00 00 41 0f b6 04 2f 84 c0 0f 85 a1 0d 00 00 0f b7 32 c1 ee 04 83 e6 0f 83 fe 04 0f 84 c7 05 00 00 83 fe 01 0f 84 78 05 00 00 <85> f6 0f 85 5a 07 00 00 48 8b 44 24 38 80 3c 28 00 74 08 4c 89 ef
RSP: 0018:ffffc90000007738 EFLAGS: 00000297
RAX: 0000000000000000 RBX: ffffc9000000783e RCX: 1ffff92000000f01
RDX: ffffffff902ac81a RSI: 0000000000000000 RDI: ffffc90000007860
RBP: dffffc0000000000 R08: 0000000000000022 R09: ffffffff8172d195
R10: ffffc90000007858 R11: ffffffff81ac4d00 R12: ffffc90003a3ff58
R13: ffffc90000007858 R14: ffffc90000007808 R15: 1ffffffff2055903
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 slab_free_after_rcu_debug+0x129/0x2a0
 rcu_core+0xcab/0x1770
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110
Code: 74 05 e8 2b dc 49 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> e3 80 12 f6 65 8b 05 6c 51 23 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc90003a3f820 EFLAGS: 00000206
RAX: ff100c4ffa24c200 RBX: 0000000000000246 RCX: ff100c4ffa24c200
RDX: 0000000000000000 RSI: ffffffff8d9bad57 RDI: 0000000000000001
RBP: ffffc90003a3f8b8 R08: ffffffff8fa3b437 R09: 1ffffffff1f47686
R10: dffffc0000000000 R11: fffffbfff1f47687 R12: dffffc0000000000
R13: ffffffff8e13f440 R14: ffffffff8e13f440 R15: 1ffff92000747f04
 rcu_report_qs_rsp+0xad/0x1b0
 rcu_preempt_deferred_qs_irqrestore+0xa11/0xce0
 rcu_read_unlock_special+0x3a2/0x4b0
 __rcu_read_unlock+0x84/0xe0
 bpf_map_update_value+0x539/0x5d0
 generic_map_update_batch+0x5b5/0x7f0
 bpf_map_do_batch+0x39b/0x630
 __sys_bpf+0x688/0x850
 __x64_sys_bpf+0x7c/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdbf6d8ec29
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:00007fdbf7b69038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fdbf6fd5fa0 RCX: 00007fdbf6d8ec29
RDX: 0000000000000038 RSI: 0000200000000500 RDI: 000000000000001a
RBP: 00007fdbf6e11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdbf6fd6038 R14: 00007fdbf6fd5fa0 R15: 00007ffed44d7ae8
 </TASK>
