------------[ cut here ]------------
conntrack cleanup blocked for 60s
WARNING: net/netfilter/nf_conntrack_core.c:2512 at nf_conntrack_cleanup_net_list+0x234/0x340, CPU#1: kworker/u8:5/27506
Modules linked in:
CPU: 1 UID: 0 PID: 27506 Comm: kworker/u8:5 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:nf_conntrack_cleanup_net_list+0x234/0x340
Code: 08 48 89 df e8 bd a9 66 f8 4c 8b 3b 49 39 df 74 69 e8 b0 73 fd f7 45 31 e4 e9 8e fe ff ff e8 a3 73 fd f7 48 8d 3d dc fe 58 06 <67> 48 0f b9 3a eb c0 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c cd fe ff
RSP: 0018:ffffc900070ef8b0 EFLAGS: 00010293
RAX: ffffffff89c8203d RBX: ffffc900070efa50 RCX: ffff8881128957c0
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: ffffffff90211f20
RBP: 0000000000000001 R08: ffff8881127e4403 R09: 1ffff110224fc880
R10: dffffc0000000000 R11: ffffed10224fc881 R12: 0000000000000001
R13: dffffc0000000000 R14: 0000000100017cad R15: 0000000100017cae
FS:  0000000000000000(0000) GS:ffff8882a9465000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000280 CR3: 0000000023638000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 ops_undo_list+0x52b/0x940
 cleanup_net+0x56b/0x800
 process_scheduled_works+0xb6e/0x18c0
 worker_thread+0xa53/0xfc0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
