rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P22209/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=274997, q=1559 ncpus=1)
task:udevd state:R running task stack:27000 pid:22209 tgid:22209 ppid:4971 task_flags:0x40014c flags:0x00080000
Call Trace:
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:539 [inline]
irqentry_exit+0x205/0xa10 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x5e/0x380 kernel/locking/lockdep.c:5947
Code: 05 cf aa a5 12 83 f8 07 0f 87 da 00 00 00 48 0f a3 05 de e7 5d 0f 0f 82 c9 02 00 00 8b 35 7e 19 5e 0f 85 f6 0f 85 c7 00 00 00 <48> 8b 44 24 30 65 48 2b 05 6d aa a5 12 0f 85 09 03 00 00 48 83 c4
RSP: 0018:ffffc900042b7580 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000200
RDX: 0000000000000000 RSI: ffffffff8e3691f1 RDI: ffffffff8c623a80
RBP: ffffffff8edec5a0 R08: 00000000cddfa937 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000001 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
__update_page_owner_free_handle.isra.0+0x4b/0x4b0 mm/page_owner.c:301
__reset_page_owner+0x93/0x190 mm/page_owner.c:339
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
free_unref_folios+0xa4a/0x1790 mm/page_alloc.c:3022
folios_put_refs+0x585/0xaa0 mm/folio.c:1036
free_pages_and_swap_cache+0x22d/0x3b0 mm/swap_state.c:592
__tlb_batch_free_encoded_pages+0xe9/0x280 mm/mmu_gather.c:138
tlb_batch_pages_flush mm/mmu_gather.c:151 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:417 [inline]
tlb_flush_mmu mm/mmu_gather.c:424 [inline]
tlb_finish_mmu+0x1b0/0x810 mm/mmu_gather.c:549
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/0x2a50 kernel/exit.c:974
do_group_exit+0xd5/0x2a0 kernel/exit.c:1129
__do_sys_exit_group kernel/exit.c:1140 [inline]
__se_sys_exit_group kernel/exit.c:1138 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1138
x64_sys_call+0x1567/0x1570 arch/x86/include/generated/asm/syscalls_64.h:232
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: 0033:0x7fcd3d0f16c5
RSP: 002b:00007fff589463d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000559ed88f82c0 RCX: 00007fcd3d0f16c5
RDX: 00000000000000e7 RSI: fffffffffffffe68 RDI: 0000000000000000
RBP: 0000559ed86732c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff58946420 R14: 0000000000000000 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 792 jiffies! g274997 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:26120 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
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
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 3223 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 08/05/2026
Workqueue: bat_events batadv_tt_purge
RIP: 0010:check_kcov_mode kernel/kcov.c:179 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x36/0x70 kernel/kcov.c:213
Code: 48 8b 34 24 65 48 8b 15 b0 d5 80 12 48 63 c8 a9 00 01 00 ff 74 1e f6 c4 01 74 44 a9 00 00 00 0f 75 3d f7 c1 00 00 00 f0 75 35 <8b> 82 44 17 00 00 85 c0 74 2b 8b 82 18 17 00 00 83 f8 02 75 20 48
RSP: 0018:ffffc90000007100 EFLAGS: 00000246
RAX: 8000000000000101 RBX: ffff888223928dc0 RCX: 0000000000000101
RDX: ffff888033b18000 RSI: ffffffff89eee497 RDI: ffff888223928dc0
RBP: dffffc0000000000 R08: 0000000000000004 R09: 0000000000000008
R10: 0000000000000003 R11: 0000000000000001 R12: 0000000000000003
R13: ffff888223928dc0 R14: ffff88807af64238 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888123b4e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055557de79a48 CR3: 0000000034030000 CR4: 00000000003526f0
Call Trace:
nf_conntrack_in+0x97/0x16d0 net/netfilter/nf_conntrack_core.c:2008
nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
nf_hook_slow+0xbf/0x220 net/netfilter/core.c:619
nf_hook include/linux/netfilter.h:280 [inline]
__ip6_local_out+0x4c0/0xaf0 net/ipv6/output_core.c:116
ip6_local_out+0x2a/0x1f0 net/ipv6/output_core.c:126
synproxy_send_tcp_ipv6+0x68d/0x7c0 net/netfilter/nf_synproxy_core.c:861
synproxy_send_client_synack_ipv6+0x601/0x7a0 net/netfilter/nf_synproxy_core.c:907
nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:90 [inline]
nft_synproxy_do_eval+0x95f/0xd30 net/netfilter/nft_synproxy.c:146
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]
ip6_input+0xe0/0x2f0 net/ipv6/ip6_input.c:545
dst_input include/net/dst.h:481 [inline]
ip6_rcv_finish net/ipv6/ip6_input.c:119 [inline]
NF_HOOK include/linux/netfilter.h:325 [inline]
NF_HOOK include/linux/netfilter.h:319 [inline]
ipv6_rcv+0x263/0x3d0 net/ipv6/ip6_input.c:351
__netif_receive_skb_one_core+0x12d/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
__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