rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=6af4/1/0x4000000000000000 softirq=14089/14089 fqs=0
rcu: 	(detected by 0, t=10502 jiffies, g=7529, q=303 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5991 Comm: syz.0.25 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:validate_chain+0x4e/0x2140
Code: 8b 46 20 89 c1 81 e1 00 80 04 00 81 f9 00 00 04 00 0f 85 61 02 00 00 41 89 d4 49 89 f6 25 ff 1f 00 00 48 0f a3 05 52 dd 0a 12 <48> 89 3c 24 72 36 83 3d c5 6c 0e 18 00 75 2d 90 e8 4d 62 27 03 85
RSP: 0018:ffffc900001e0638 EFLAGS: 00000003
RAX: 0000000000000067 RBX: 0000000000000004 RCX: 0000000000040000
RDX: 0000000000000001 RSI: ffff88801ef22850 RDI: ffff88801ef21cc0
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff81ada78b
R10: dffffc0000000000 R11: ffffed1026cc4f51 R12: 0000000000000001
R13: ffff88801ef227b0 R14: ffff88801ef22850 R15: d6bf87c490213bdc
FS:  00007f0d59b996c0(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000010f72e000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 __lock_acquire+0xab9/0xd20
 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:unwind_next_frame+0x132b/0x2390
Code: b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 27 49 63 07 4c 01 f8 49 8d 4f 04 4c 39 e0 48 0f 46 e9 49 8d 47 fc 48 0f 47 d8 <4d> 0f 46 ef 48 39 dd 76 a2 e9 7b ef ff ff 44 89 f9 80 e1 07 80 c1
RSP: 0018:ffffc9000489f298 EFLAGS: 00000297
RAX: ffffffff8fc13d10 RBX: ffffffff8fc13d14 RCX: ffffffff8fc13d18
RDX: ffffffff8fc13d14 RSI: ffffffff90421d78 RDI: ffffffff8be33da0
RBP: ffffffff8fc13d18 R08: 0000000000000001 R09: ffffffff8172d195
R10: ffffc9000489f3b8 R11: ffffffff81ac4d00 R12: ffffffff8234934b
R13: ffffffff8fc13d14 R14: ffffc9000489f368 R15: ffffffff8fc13d14
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_stack+0x3e/0x60
 kasan_record_aux_stack+0xbd/0xd0
 call_rcu+0x157/0x9c0
 delete_node+0x1b6/0xa50
 radix_tree_delete_item+0x2b6/0x400
 conn_put+0x98/0x320
 tipc_group_delete+0x40c/0x480
 tipc_sk_leave+0x138/0x4e0
 tipc_release+0x5fc/0x2190
 sock_close+0xc3/0x240
 __fput+0x44c/0xa70
 fput_close_sync+0x119/0x200
 __x64_sys_close+0x7f/0x110
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0d58d8eba9
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:00007f0d59b99038 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00007f0d58fd5fa0 RCX: 00007f0d58d8eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 00007f0d58e11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0d58fd6038 R14: 00007f0d58fd5fa0 R15: 00007fff4d0648b8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g7529 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=2893
rcu: rcu_preempt kthread starved for 10502 jiffies! g7529 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27120 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>
