rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=4464/1/0x4000000000000000 softirq=57539/57539 fqs=0
rcu: 	(detected by 1, t=10506 jiffies, g=43873, q=11841 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13590 Comm: syz.8.2085 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+0x61/0xd20
Code: 00 00 41 89 cc 41 89 d6 8b 0d ab 3a 63 0c 85 c9 44 0f 44 c1 31 c9 48 3d 10 93 64 93 41 0f 45 c8 89 4c 24 0c 8b 0d 8f af 0e 18 <85> c9 0f 95 c0 83 fe 08 0f 92 c2 08 c2 0f 84 55 01 00 00 44 89 cd
RSP: 0018:ffffc90000007310 EFLAGS: 00000087
RAX: ffff88804b027a98 RBX: ffff88804b027a98 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88801f7e1cc0
RBP: ffffffff81ada78b R08: 0000000000000001 R09: 0000000000000001
R10: dffffc0000000000 R11: ffffed1009604f51 R12: 0000000000000000
R13: ffff88804b027a98 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f9493e7a6c0(0000) GS:ffff8880b8613000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000009b00 CR3: 000000003f210000 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:_raw_spin_unlock_irq+0x29/0x50
Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 1a 91 20 f6 48 89 df e8 72 28 21 f6 e8 0d 7b 4a f6 fb bf 01 00 00 00 <e8> 42 20 13 f6 65 8b 05 cb e0 23 07 85 c0 74 07 5b c3 cc cc cc cc
RSP: 0018:ffffc90000007c90 EFLAGS: 00000286
RAX: d61ff8d0c4cf7400 RBX: ffff88804b025900 RCX: d61ff8d0c4cf7400
RDX: 0000000000000002 RSI: ffffffff8d9ba18e RDI: 0000000000000001
RBP: ffffc90000007e10 R08: ffffffff8fa3a837 R09: 1ffffffff1f47506
R10: dffffc0000000000 R11: fffffbfff1f47507 R12: dffffc0000000000
R13: ffff88804b025948 R14: 0000000000000000 R15: 0000000000000000
 __run_timer_base+0x1ad/0x860
 run_timer_softirq+0xb7/0x180
 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:synproxy_pernet+0x39/0x270
Code: 00 00 00 fc ff df e8 66 9b f9 f7 48 c7 c0 c0 73 fe 99 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 17 02 00 00 44 8b 25 07 4e 38 10 <e8> c2 05 e1 f7 48 8d 1d 00 00 00 00 48 c7 c7 20 a1 13 8e 31 f6 31
RSP: 0018:ffffc90007a670b0 EFLAGS: 00000297
RAX: 0000000000000004 RBX: ffffc90007a67240 RCX: ffffffff99fe7303
RDX: 0000000000000000 RSI: ffff88810b553118 RDI: ffff8880437a8000
RBP: 1ffff92000f4ce48 R08: ffff88801f7e1cc0 R09: 0000000000000007
R10: 0000000000000016 R11: ffffffff89c611b0 R12: 0000000000000031
R13: dffffc0000000000 R14: ffff8880437a8000 R15: dffffc0000000000
 nft_synproxy_do_destroy+0x3c/0x180
 nf_tables_abort+0x7cba/0x88a0
 nfnetlink_rcv+0x1ca3/0x2520
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 ____sys_sendmsg+0x505/0x830
 ___sys_sendmsg+0x21f/0x2a0
 __x64_sys_sendmsg+0x19b/0x260
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9492f8eba9
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:00007f9493e7a038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f94931d5fa0 RCX: 00007f9492f8eba9
RDX: 0000000024044010 RSI: 0000200000000100 RDI: 0000000000000005
RBP: 00007f9493011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f94931d6038 R14: 00007f94931d5fa0 R15: 00007ffd32f06b38
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g43873 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=30024
rcu: rcu_preempt kthread starved for 10506 jiffies! g43873 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:26728 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>
