rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P27106/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=158141, q=314 ncpus=2)
task:kworker/0:6 state:R running task stack:27352 pid:27106 ppid:2 flags:0x00004000
Workqueue: events_power_efficient gc_worker
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7010
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:seqcount_lockdep_reader_access+0x19a/0x1d0 include/linux/seqlock.h:105
Code: f8 4d 85 e4 75 16 e8 e5 67 ca f8 eb 15 e8 de 67 ca f8 e8 f9 4c c9 01 4d 85 e4 74 ea e8 cf 67 ca f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 43 c7 44 3e 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc90003ad79a0 EFLAGS: 00000293
RAX: ffffffff88bcb851 RBX: 0000000000000000 RCX: ffff888024b68000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003ad7a50 R08: ffffffff911c3597 R09: 1ffffffff22386b2
R10: dffffc0000000000 R11: fffffbfff22386b3 R12: 0000000000000200
R13: dffffc0000000000 R14: 1ffff9200075af34 R15: dffffc0000000000
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:350 [inline]
gc_worker+0x317/0x1490 net/netfilter/nf_conntrack_core.c:1504
process_one_work kernel/workqueue.c:2653 [inline]
process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: rcu_preempt kthread starved for 5011 jiffies! g158141 f0x0 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:26440 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x1553/0x45a0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x313/0x1590 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:preempt_count_sub+0x27/0x160 kernel/sched/core.c:5873
Code: 1f 40 00 f3 0f 1e fa 55 53 48 bb 00 00 00 00 00 fc ff df 48 c7 c0 80 a4 2c 97 48 c1 e8 03 0f b6 04 18 84 c0 0f 85 bd 00 00 00 <83> 3d 02 1c d0 15 00 75 25 65 8b 05 41 2d a7 7e 89 c1 81 e1 ff ff
RSP: 0018:ffffc900000063b8 EFLAGS: 00000297
RAX: 0000000000000004 RBX: dffffc0000000000 RCX: ffffffff972ca403
RDX: 0000000000000100 RSI: ffffc900000064a0 RDI: 0000000000000001
RBP: ffffc900000064a0 R08: ffffffff8ce93440 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000100 R12: ffffc90000006508
R13: dffffc0000000000 R14: ffffc90000006508 R15: ffffc90000006518
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000077f030 CR3: 000000002f6ec000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000001800
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
unwind_next_frame+0x1d07/0x2970 arch/x86/kernel/unwind_orc.c:672
__unwind_start+0x66a/0x7e0 arch/x86/kernel/unwind_orc.c:760
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xf8/0x190 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
kmem_cache_free+0xf8/0x270 mm/slub.c:3852
enqueue_to_backlog+0x1d2/0xe30 net/core/dev.c:4908
netif_rx_internal+0x119/0x4e0 net/core/dev.c:5164
__netif_rx+0x78/0xc0 net/core/dev.c:5184
loopback_xmit+0x41a/0x630 drivers/net/loopback.c:89
__netdev_start_xmit include/linux/netdevice.h:4943 [inline]
netdev_start_xmit include/linux/netdevice.h:4957 [inline]
xmit_one net/core/dev.c:3632 [inline]
dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3648
sch_direct_xmit+0x25e/0x4c0 net/sched/sch_generic.c:345
qdisc_restart net/sched/sch_generic.c:410 [inline]
__qdisc_run+0xa56/0x1500 net/sched/sch_generic.c:418
__dev_xmit_skb net/core/dev.c:3932 [inline]
__dev_queue_xmit+0x10ad/0x3660 net/core/dev.c:4404
dev_queue_xmit include/linux/netdevice.h:3113 [inline]
neigh_hh_output include/net/neighbour.h:527 [inline]
neigh_output include/net/neighbour.h:541 [inline]
ip_finish_output2+0xcec/0x11e0 net/ipv4/ip_output.c:235
NF_HOOK_COND include/linux/netfilter.h:293 [inline]
ip_output+0x2a1/0x3b0 net/ipv4/ip_output.c:436
synproxy_send_client_synack+0x890/0xde0 net/netfilter/nf_synproxy_core.c:484
nft_synproxy_eval_v4+0x34b/0x4e0 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x306/0x570 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline]
nft_do_chain+0x44e/0x1600 net/netfilter/nf_tables_core.c:288
nft_do_chain_inet+0x29b/0x380 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline]
nf_hook_slow+0xbd/0x200 net/netfilter/core.c:626
nf_hook include/linux/netfilter.h:259 [inline]
NF_HOOK+0x21d/0x3b0 include/linux/netfilter.h:302
NF_HOOK+0x32d/0x3b0 include/linux/netfilter.h:304
__netif_receive_skb_one_core net/core/dev.c:5634 [inline]
__netif_receive_skb+0xcc/0x290 net/core/dev.c:5748
process_backlog+0x391/0x6f0 net/core/dev.c:6076
__napi_poll+0xc0/0x460 net/core/dev.c:6638
napi_poll net/core/dev.c:6705 [inline]
net_rx_action+0x616/0xc40 net/core/dev.c:6841
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:pv_native_safe_halt+0xf/0x10 arch/x86/kernel/paravirt.c:148
Code: 6f 21 02 c3 cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 23 39 42 00 fb f4 66 0f 1f 00 55 41 57 41 56 41 54 53 50 8b 2f eb 2e 41 89 de 80
RSP: 0018:ffffffff8ce07d80 EFLAGS: 000002c6
RAX: dfbcf4e672c45900 RBX: ffffffff8162a8c1 RCX: dfbcf4e672c45900
RDX: 0000000000000001 RSI: ffffffff8acac9e0 RDI: ffffffff8b1c89a0
RBP: ffffffff8ce07eb8 R08: ffff8880b8e36b2b R09: 1ffff110171c6d65
R10: dffffc0000000000 R11: ffffed10171c6d66 R12: 1ffffffff19c0fbc
R13: dffffc0000000000 R14: 1ffffffff19d2688 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:753
default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
cpuidle_idle_call kernel/sched/idle.c:178 [inline]
do_idle+0x221/0x590 kernel/sched/idle.c:302
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:401
rest_init+0x2e2/0x300 init/main.c:744
arch_call_rest_init+0xe/0x10 init/main.c:841
start_kernel+0x459/0x4e0 init/main.c:1086
x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555
x86_64_start_kernel+0x60/0x60 arch/x86/kernel/head64.c:536
secondary_startup_64_no_verify+0x179/0x17b