rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P18060/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=103669, q=503961 ncpus=2)
task:syz.3.3253 state:R running task stack:25576 pid:18060 tgid:18060 ppid:5841 task_flags:0x40004c flags:0x10080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256
irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:127 [inline]
RIP: 0010:lock_acquire+0xc9/0x360 kernel/locking/lockdep.c:5864
Code: d1 10 85 c0 0f 85 eb 00 00 00 65 48 8b 04 25 08 20 6e 92 83 b8 2c 0b 00 00 00 0f 85 d5 00 00 00 48 c7 44 24 30 00 00 00 00 9c <8f> 44 24 30 4c 89 74 24 10 4d 89 fe 4c 8b 7c 24 30 fa 48 c7 c7 e1
RSP: 0018:ffffc9000ea4f420 EFLAGS: 00000246
RAX: ffff88801c701e40 RBX: 0000000000000000 RCX: e1938f50950d8a00
RDX: 0000000000000000 RSI: ffffffff8230cd67 RDI: 1ffffffff1be7a9c
RBP: ffffffff8230cd4a R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed10062cf28a R12: 0000000000000002
R13: ffffffff8df3d4e0 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
__page_table_check_zero+0xd7/0x530 mm/page_table_check.c:138
page_table_check_free include/linux/page_table_check.h:43 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
free_unref_folios+0xdc7/0x14f0 mm/page_alloc.c:2963
folios_put_refs+0x584/0x670 mm/swap.c:1002
free_pages_and_swap_cache+0x277/0x520 mm/swap_state.c:355
__tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
exit_mmap+0x444/0xb40 mm/mmap.c:1293
__mmput+0x118/0x430 kernel/fork.c:1133
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:954
do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
__do_sys_exit_group kernel/exit.c:1118 [inline]
__se_sys_exit_group kernel/exit.c:1116 [inline]
__ia32_sys_exit_group+0x3f/0x40 kernel/exit.c:1116
ia32_sys_call+0x21f4/0x2200 arch/x86/include/generated/asm/syscalls_32.h:253
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0xb6/0x2b0 arch/x86/entry/syscall_32.c:306
do_fast_syscall_32+0x34/0x80 arch/x86/entry/syscall_32.c:331
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7fe1539
RSP: 002b:00000000f75cfd4c EFLAGS: 00000206 ORIG_RAX: 00000000000000fc
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000ffffff9c RDI: 00000000f7475ff4
RBP: 000000000000002c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 7927 jiffies! g103669 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:27288 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7026
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
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: 60 Comm: kworker/u8:4 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:nf_nat_packet net/netfilter/nf_nat_core.c:898 [inline]
RIP: 0010:nf_nat_inet_fn+0x8f0/0xba0 net/netfilter/nf_nat_core.c:982
Code: e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 26 a3 ab f8 45 23 3c 24 31 ff 4c 89 fe e8 d8 f2 45 f8 45 85 ff 4c 8b 6c 24 28 <4c> 8b 74 24 40 74 28 45 31 ff 83 7c 24 20 03 41 0f 93 c7 e8 d8 ed
RSP: 0018:ffffc90000006be0 EFLAGS: 00000246
RAX: ffffffff897a1888 RBX: 0000000000000001 RCX: ffff88801c311e40
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000006d10 R08: ffff88801c311e40 R09: 0000000000000005
R10: 0000000000000004 R11: 0000000000000100 R12: ffff888023c698c0
R13: 1ffff92000000d88 R14: 0000000000000003 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88812613e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000008001c000 CR3: 000000006d440000 CR4: 00000000003526f0
Call Trace:
nf_nat_ipv6_fn+0x21d/0x2d0 net/netfilter/nf_nat_proto.c:931
nf_nat_ipv6_local_fn+0x2e/0x3a0 net/netfilter/nf_nat_proto.c:1017
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:273 [inline]
__ip6_local_out+0x763/0x870 net/ipv6/output_core.c:145
ip6_local_out+0x26/0x70 net/ipv6/output_core.c:155
synproxy_send_tcp_ipv6+0x543/0x700 net/netfilter/nf_synproxy_core.c:851
synproxy_send_client_synack_ipv6+0x80e/0xca0 net/netfilter/nf_synproxy_core.c:897
nft_synproxy_eval_v6+0x36e/0x560 net/netfilter/nft_synproxy.c:90
nft_synproxy_do_eval+0x3d7/0x570 net/netfilter/nft_synproxy.c:145
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x40c/0x1920 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:273 [inline]
NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316
ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:500
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6079 [inline]
__netif_receive_skb+0xd3/0x380 net/core/dev.c:6192
process_backlog+0x60e/0x14f0 net/core/dev.c:6544
__napi_poll+0xc7/0x360 net/core/dev.c:7594
napi_poll net/core/dev.c:7657 [inline]
net_rx_action+0x5f7/0xdf0 net/core/dev.c:7784
handle_softirqs+0x286/0x870 kernel/softirq.c:622
do_softirq+0xec/0x180 kernel/softirq.c:523
__local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:450
ieee80211_rx_bss_info net/mac80211/ibss.c:1166 [inline]
ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1573 [inline]
ieee80211_ibss_rx_queued_mgmt+0x11fd/0x2af0 net/mac80211/ibss.c:1600
ieee80211_iface_process_skb net/mac80211/iface.c:1694 [inline]
ieee80211_iface_work+0x85f/0x12d0 net/mac80211/iface.c:1748
cfg80211_wiphy_work+0x2bb/0x470 net/wireless/core.c:435
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245