rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5586/1:b..l P8819/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=44565, q=1234 ncpus=1)
task:syz.3.929       state:R  running task     stack:26392 pid:8819  tgid:8819  ppid:5598   task_flags:0x40044c flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5533 [inline]
 __schedule+0x1259/0x6920 kernel/sched/core.c:7284
 preempt_schedule_notrace+0x57/0xd0 kernel/sched/core.c:7556
 preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
 rcu_is_watching+0x90/0xc0 kernel/rcu/tree.c:754
 rcu_read_lock include/linux/rcupdate.h:850 [inline]
 is_bpf_text_address+0xa7/0x1a0 kernel/bpf/core.c:750
 kernel_text_address kernel/extable.c:125 [inline]
 kernel_text_address+0x8d/0x100 kernel/extable.c:94
 __kernel_text_address+0xd/0x30 kernel/extable.c:79
 unwind_get_return_address+0x59/0xa0 arch/x86/kernel/unwind_orc.c:385
 arch_stack_walk+0xa6/0xf0 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 save_stack+0x162/0x1e0 mm/page_owner.c:183
 __reset_page_owner+0x84/0x190 mm/page_owner.c:338
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
 tlb_batch_list_free mm/mmu_gather.c:161 [inline]
 tlb_finish_mmu+0x27d/0x810 mm/mmu_gather.c:552
 exit_mmap+0x454/0xa00 mm/mmap.c:1328
 __mmput+0x12a/0x410 kernel/fork.c:1193
 mmput+0x67/0x80 kernel/fork.c:1216
 exit_mm kernel/exit.c:592 [inline]
 do_exit+0x83b/0x2a60 kernel/exit.c:974
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1129
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3112
 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x139/0x700 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
 do_syscall_64+0x661/0x790 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2882b9f349
RSP: 002b:00007fff601f93e8 EFLAGS: 00000202 ORIG_RAX: 00000000000001b3
RAX: fffffffffffffffc RBX: 00007f2882b5a8e0 RCX: 00007f2882b9f349
RDX: 00007f2882b5a8e0 RSI: 0000000000000058 RDI: 00007fff601f9440
RBP: 00007f28839c06c0 R08: 00007f28839c06c0 R09: 00007fff601f9527
R10: 0000000000000008 R11: 0000000000000202 R12: ffffffffffffffe8
R13: 000000000000006e R14: 00007fff601f9440 R15: 00007fff601f9528
 </TASK>
task:syz-executor    state:R  running task     stack:21864 pid:5586  tgid:5586  ppid:5585   task_flags:0x400100 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5533 [inline]
 __schedule+0x1259/0x6920 kernel/sched/core.c:7284
 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:7606
 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline]
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:558 [inline]
 irqentry_exit+0x247/0xa90 kernel/entry/common.c:167
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_release+0x19e/0x310 kernel/locking/lockdep.c:5968
Code: ff 65 0f c1 05 db 5d a6 13 83 f8 01 0f 85 27 01 00 00 9c 58 f6 c4 02 0f 85 12 01 00 00 41 f7 c6 00 02 00 00 0f 85 c8 00 00 00 <48> 8b 44 24 10 65 48 2b 05 dd 16 a6 13 0f 85 4d 01 00 00 48 83 c4
RSP: 0018:ffffc90003f5f860 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8fdec620 RCX: ffffc90003f5f86c
RDX: 0000000000000000 RSI: ffffffff8e3bd91c RDI: ffffffff8c625680
RBP: ffffffff81b9c54e R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 000000000001987d R12: ffff88803110a580
R13: ffffc90003f5f918 R14: 0000000000000202 R15: 0000000000000002
 rcu_lock_release include/linux/rcupdate.h:319 [inline]
 rcu_read_unlock include/linux/rcupdate.h:880 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1216 [inline]
 unwind_next_frame+0x3c3/0x2090 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 save_stack+0x162/0x1e0 mm/page_owner.c:183
 __reset_page_owner+0x84/0x190 mm/page_owner.c:338
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:361
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4683 [inline]
 slab_alloc_node mm/slub.c:4996 [inline]
 kmem_cache_alloc_noprof+0x269/0x6a0 mm/slub.c:5010
 alloc_empty_file+0x5b/0x1c0 fs/file_table.c:262
 alloc_file fs/file_table.c:396 [inline]
 alloc_file_pseudo+0x183/0x290 fs/file_table.c:427
 create_pipe_files+0x360/0x970 fs/pipe.c:1027
 __do_pipe_flags fs/pipe.c:1073 [inline]
 do_pipe2+0xbd/0x1e0 fs/pipe.c:1121
 __do_sys_pipe2 fs/pipe.c:1139 [inline]
 __se_sys_pipe2 fs/pipe.c:1137 [inline]
 __x64_sys_pipe2+0x54/0x80 fs/pipe.c:1137
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbafd99d589
RSP: 002b:00007ffc2f231958 EFLAGS: 00000246 ORIG_RAX: 0000000000000125
RAX: ffffffffffffffda RBX: 000055555ac86ed0 RCX: 00007fbafd99d589
RDX: 0000000000000008 RSI: 0000000000000000 RDI: 00007ffc2f231968
RBP: 00007ffc2f231f40 R08: 00007fbafdbf6e20 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc2f231d80
R13: 000055555acf8378 R14: 000055555ac8b460 R15: 00007ffc2f231ac0
 </TASK>
rcu: rcu_preempt kthread starved for 4670 jiffies! g44565 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27560 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5533 [inline]
 __schedule+0x1259/0x6920 kernel/sched/core.c:7284
 __schedule_loop kernel/sched/core.c:7361 [inline]
 schedule+0xdd/0x2c0 kernel/sched/core.c:7376
 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1a9/0x8f0 kernel/rcu/tree.c:2122
 rcu_gp_kthread+0x17a/0x220 kernel/rcu/tree.c:2330
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 3222 Comm: kworker/R-bat_e Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Workqueue: bat_events batadv_tt_purge
RIP: 0010:__rcu_read_lock+0x0/0x70 kernel/rcu/tree_plugin.h:413
Code: fd ff ff 48 89 ef e8 0f 97 90 00 e9 c0 fd ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 b8 00 00 00 00 00 fc ff df 53 65 48 8b 1d 91 9c 9d
RSP: 0018:ffffc90000007160 EFLAGS: 00000246
RAX: ffffc90000007730 RBX: 0000000000000002 RCX: ffffc9000000712c
RDX: 1ffff92000000e42 RSI: ffffffff89fa72f5 RDI: ffffc900000071d8
RBP: ffffc90000007220 R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000090943 R12: ffffffff81f62140
R13: ffffc900000071d8 R14: 0000000000000000 R15: ffff88803672a580
FS:  0000000000000000(0000) GS:ffff888122946000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbafabf10d8 CR3: 000000005d3cf000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_read_lock include/linux/rcupdate.h:847 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
 unwind_next_frame+0xae/0x2090 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:264 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:296
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2748 [inline]
 slab_free mm/slub.c:6509 [inline]
 kmem_cache_free+0x127/0x6c0 mm/slub.c:6636
 kfree_skbmem+0x19a/0x210 net/core/skbuff.c:1145
 __kfree_skb net/core/skbuff.c:1212 [inline]
 consume_skb net/core/skbuff.c:1448 [inline]
 consume_skb+0xd1/0x110 net/core/skbuff.c:1442
 nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:60 [inline]
 nft_synproxy_do_eval+0xa72/0xd30 net/netfilter/nft_synproxy.c:142
 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
 nft_do_chain+0x2e5/0x19d0 net/netfilter/nf_tables_core.c:285
 nft_do_chain_inet+0xf3/0x400 net/netfilter/nft_chain_filter.c:162
 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
 nf_hook_slow+0xbf/0x220 net/netfilter/core.c:619
 nf_hook.constprop.0+0x2a6/0x750 include/linux/netfilter.h:280
 NF_HOOK include/linux/netfilter.h:323 [inline]
 ip_local_deliver+0x163/0x1f0 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:481 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:492 [inline]
 NF_HOOK include/linux/netfilter.h:325 [inline]
 NF_HOOK include/linux/netfilter.h:319 [inline]
 ip_rcv+0x33a/0x3c0 net/ipv4/ip_input.c:612
 __netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6297
 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6410
 process_backlog+0x487/0x1600 net/core/dev.c:6761
 __napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7830
 napi_poll net/core/dev.c:7893 [inline]
 net_rx_action+0xa40/0xf20 net/core/dev.c:8050
 handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
 do_softirq kernel/softirq.c:546 [inline]
 do_softirq+0xaf/0xf0 kernel/softirq.c:533
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0xff/0x120 kernel/softirq.c:473
 spin_unlock_bh include/linux/spinlock.h:407 [inline]
 batadv_tt_global_purge net/batman-adv/translation-table.c:2390 [inline]
 batadv_tt_purge+0x25d/0xbd0 net/batman-adv/translation-table.c:3754
 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
 process_scheduled_works kernel/workqueue.c:3479 [inline]
 rescuer_thread+0x918/0x14e0 kernel/workqueue.c:3703
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>