rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P14234/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=83721, q=856241 ncpus=2)
task:syz.6.2350      state:R  running task     stack:25512 pid:14234 tgid:14226 ppid:12472  task_flags:0x40044c flags:0x00080000
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 preempt_schedule_irq+0x4d/0xa0
 irqentry_exit+0x14f/0x730
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:lock_acquire+0x221/0x350
Code: ff ff ff e8 a1 07 16 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 8b 92 9e 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 48 8d 3d 58 00 95
RSP: 0018:ffffc900046e6f78 EFLAGS: 00000286
RAX: 5862a8b0607b4300 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000002ad94000 RSI: ffffffff8e24b9a6 RDI: ffffffff8c289f60
RBP: ffffffff81770256 R08: ffffffff81770256 R09: ffffffff8e95cce0
R10: ffffc900046e70d8 R11: ffffffff81b0f610 R12: 0000000000000002
R13: ffffffff8e95cce0 R14: 0000000000000000 R15: 0000000000000246
 unwind_next_frame+0xc3/0x2550
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 save_stack+0x122/0x230
 __reset_page_owner+0x71/0x1f0
 free_unref_folios+0xcec/0x1480
 folios_put_refs+0x9ff/0xb40
 free_pages_and_swap_cache+0x2b9/0x490
 tlb_flush_mmu+0x6d3/0xa30
 tlb_finish_mmu+0xf9/0x230
 exit_mmap+0x498/0x9e0
 __mmput+0x118/0x430
 exit_mm+0x18e/0x250
 do_exit+0x6a2/0x22c0
 do_group_exit+0x21b/0x2d0
 get_signal+0x1284/0x1330
 arch_do_signal_or_restart+0xbc/0x830
 exit_to_user_mode_loop+0x86/0x480
 do_syscall_64+0x33e/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f773c19c819
RSP: 002b:00007f773d10d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: 000000000000000f RBX: 00007f773c416090 RCX: 00007f773c19c819
RDX: 0000000000000001 RSI: 0000200000000140 RDI: ffffffffffffff9c
RBP: 00007f773c232c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f773c416128 R14: 00007f773c416090 R15: 00007ffe421dc9b8
 </TASK>
rcu: rcu_preempt kthread starved for 486 jiffies! g83721 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:27544 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_timeout+0x158/0x2c0
 rcu_gp_fqs_loop+0x312/0x11d0
 rcu_gp_kthread+0x9e/0x2b0
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 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: 13 Comm: kworker/u8:1 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: bat_events batadv_tt_purge
RIP: 0010:__sanitizer_cov_trace_pc+0x2e/0x70
Code: 48 8b 04 24 65 48 8b 0d 88 90 7a 11 65 8b 15 a9 90 7a 11 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 cc 16 00 00 00 <74> 2c 8b 91 a8 16 00 00 83 fa 02 75 21 48 8b 91 b0 16 00 00 48 8b
RSP: 0018:ffffc90000007118 EFLAGS: 00000246
RAX: ffffffff8a14f5da RBX: dffffc0000000000 RCX: ffff888102af5880
RDX: 0000000000000100 RSI: ffffffff8c289f40 RDI: ffffffff8c289f00
RBP: ffffc90000007238 R08: ffffffff8a14f591 R09: ffffffff8e95cce0
R10: 0000000000000003 R11: 0000000000000100 R12: 1ffff92000000e2c
R13: ffff8881bae94d80 R14: 0000000000000001 R15: ffff888073b24180
FS:  0000000000000000(0000) GS:ffff88818dc1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa7df4d72c0 CR3: 00000001123d6000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 nf_hook+0xea/0x3a0
 ip_output+0x269/0x450
 synproxy_send_client_synack+0x8c1/0xe30
 nft_synproxy_eval_v4+0x34a/0x4e0
 nft_synproxy_do_eval+0x305/0x580
 nft_do_chain+0x467/0x19f0
 nft_do_chain_inet+0x360/0x4b0
 nf_hook_slow+0xc5/0x220
 NF_HOOK+0x21f/0x3c0
 NF_HOOK+0x336/0x3c0
 process_backlog+0xaa3/0x1950
 __napi_poll+0xae/0x340
 net_rx_action+0x627/0xf70
 handle_softirqs+0x22a/0x840
 do_softirq+0x76/0xd0
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0xf8/0x130
 batadv_tt_purge+0x4d1/0x9e0
 process_scheduled_works+0xb5d/0x1860
 worker_thread+0xa53/0xfc0
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>
