rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P38/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=50581, q=3414 ncpus=2)
task:khugepaged state:R running task stack:28104 pid:38 tgid:38 ppid:2 task_flags:0x200040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:7047
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__folio_batch_add_and_move+0x5e2/0xc30 mm/swap.c:201
folio_putback_lru+0x1c/0xd0 mm/vmscan.c:847
__collapse_huge_page_copy_succeeded mm/khugepaged.c:715 [inline]
__collapse_huge_page_copy mm/khugepaged.c:810 [inline]
collapse_huge_page+0x22b7/0x3420 mm/khugepaged.c:1214
hpage_collapse_scan_pmd+0xd4b/0x13d0 mm/khugepaged.c:1407
khugepaged_scan_mm_slot mm/khugepaged.c:2486 [inline]
khugepaged_do_scan mm/khugepaged.c:2570 [inline]
khugepaged+0x1228/0x1690 mm/khugepaged.c:2626
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: rcu_preempt kthread starved for 248 jiffies! g50581 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:27920 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
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: 34 Comm: kcompactd0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:hlock_class kernel/locking/lockdep.c:229 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4879 [inline]
RIP: 0010:__lock_acquire+0x326/0x2890 kernel/locking/lockdep.c:5187
Code: 0f b6 81 c4 00 00 00 84 c0 74 0f 38 c2 0f 47 d0 80 b9 c6 00 00 00 02 0f 44 d0 83 c3 01 41 3b 9c 24 28 0b 00 00 7d 30 48 63 c3 <48> 8d 04 80 41 0f b7 44 c3 20 66 25 ff 1f 0f b7 c0 48 0f a3 05 21
RSP: 0018:ffffc90000007078 EFLAGS: 00000006
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000020
RDX: 0000000000000003 RSI: 0000000000000003 RDI: ffffffff8e3c9620
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000007
R10: 0000000000000000 R11: ffff88801f2c8b30 R12: ffff88801f2c8000
R13: 0000000000000001 R14: ffff88801f2c8ba8 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881248f6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558a2e05c8 CR3: 00000000603b1000 CR4: 00000000003526f0
Call Trace:
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x179/0x330 kernel/locking/lockdep.c:5825
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
netlbl_skbuff_setattr+0x43/0x500 net/netlabel/netlabel_kapi.c:1319
selinux_netlbl_skbuff_setsid+0x2e6/0x5e0 security/selinux/netlabel.c:259
selinux_ip_output+0x1f1/0x2a0 security/selinux/hooks.c:5938
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623
nf_hook+0x371/0x680 include/linux/netfilter.h:273
__ip_local_out+0x33a/0x7c0 net/ipv4/ip_output.c:120
ip_local_out+0x2e/0x4d0 net/ipv4/ip_output.c:129
synproxy_send_tcp.isra.0+0x491/0x6a0 net/netfilter/nf_synproxy_core.c:439
synproxy_send_client_synack+0x6f6/0x8f0 net/netfilter/nf_synproxy_core.c:484
nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:59 [inline]
nft_synproxy_do_eval+0xa63/0xd80 net/netfilter/nft_synproxy.c:141
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x2e9/0x1920 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0x18a/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xbe/0x200 net/netfilter/core.c:623
nf_hook.constprop.0+0x424/0x750 include/linux/netfilter.h:273
NF_HOOK include/linux/netfilter.h:316 [inline]
ip_local_deliver+0x169/0x1f0 net/ipv4/ip_input.c:262
dst_input include/net/dst.h:474 [inline]
ip_rcv_finish net/ipv4/ip_input.c:453 [inline]
NF_HOOK include/linux/netfilter.h:318 [inline]
NF_HOOK include/linux/netfilter.h:312 [inline]
ip_rcv+0x2e0/0x600 net/ipv4/ip_input.c:573
__netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6137
__netif_receive_skb+0x1d/0x160 net/core/dev.c:6250
process_backlog+0x4a2/0x1650 net/core/dev.c:6602
__napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7666
napi_poll net/core/dev.c:7729 [inline]
net_rx_action+0x9f9/0xfa0 net/core/dev.c:7881
handle_softirqs+0x219/0x950 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xdfd/0x15e0 kernel/smp.c:877
Code: 57 48 8b 54 24 10 4c 89 74 24 10 49 89 d5 48 89 d5 48 89 54 24 18 49 c1 ed 03 83 e5 07 4d 01 e5 83 c5 03 e8 35 5b 0c 00 f3 90 <41> 0f b6 45 00 40 38 c5 7c 08 84 c0 0f 85 b6 05 00 00 8b 43 08 31
RSP: 0018:ffffc90000aa7268 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b8540cc0 RCX: ffffffff81b28b81
RDX: ffff88801f2c8000 RSI: ffffffff81b28b5b RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: ffff88801f2c8b30 R12: dffffc0000000000
R13: ffffed10170a8199 R14: 0000000000000001 R15: 0000000000000001
on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1043
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
arch_tlbbatch_flush+0x253/0x370 arch/x86/mm/tlb.c:1746
try_to_unmap_flush+0x6a/0xf0 mm/rmap.c:625
migrate_pages_batch+0x2ddc/0x3bb0 mm/migrate.c:1968
migrate_pages_sync+0x12d/0x8a0 mm/migrate.c:2007
migrate_pages+0x1b0b/0x2350 mm/migrate.c:2116
compact_zone+0x1e78/0x4540 mm/compaction.c:2647
kcompactd_do_work+0x35c/0x6f0 mm/compaction.c:3098
kcompactd+0x406/0xe80 mm/compaction.c:3192
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246