rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9146/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=45833, q=1338531 ncpus=2)
task:udevd state:R running task stack:25832 pid:9146 tgid:9146 ppid:5176 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7234
irqentry_exit+0x17b/0x670 kernel/entry/common.c:239
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:124 [inline]
RIP: 0010:lock_release+0x6d/0x320 kernel/locking/lockdep.c:5881
Code: 02 00 00 44 8b 05 b7 c8 f4 0e 45 85 c0 0f 84 48 01 00 00 65 8b 05 2b f9 28 12 85 c0 0f 85 39 01 00 00 65 4c 8b 25 ab b1 28 12 <41> 8b bc 24 14 0b 00 00 85 ff 0f 85 21 01 00 00 48 81 3b 40 57 14
RSP: 0018:ffffc900065c7870 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff8e7e93e0 RCX: ffffffff922c6401
RDX: 0000000000000000 RSI: ffffffff8c1aef20 RDI: ffffffff8e1238e8
RBP: ffffffff81b7fdde R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 00000000000a8ef1 R12: ffff888023b3a480
R13: ffffc900065c7928 R14: ffffc900065c7f48 R15: ffffc900065c795c
rcu_lock_release include/linux/rcupdate.h:322 [inline]
rcu_read_unlock include/linux/rcupdate.h:881 [inline]
class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0x3c3/0x1ea0 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:165
__reset_page_owner+0x84/0x190 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1433 [inline]
__free_frozen_pages+0x7e1/0x10d0 mm/page_alloc.c:2978
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4501 [inline]
slab_alloc_node mm/slub.c:4830 [inline]
kmem_cache_alloc_noprof+0x241/0x6e0 mm/slub.c:4837
alloc_filename fs/namei.c:142 [inline]
do_getname+0x35/0x390 fs/namei.c:182
getname include/linux/fs.h:2512 [inline]
getname_maybe_null include/linux/fs.h:2519 [inline]
class_filename_maybe_null_constructor include/linux/fs.h:2543 [inline]
vfs_fstatat+0xd0/0xe0 fs/stat.c:368
__do_sys_newfstatat+0x9d/0x120 fs/stat.c:538
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f89fe111b0a
RSP: 002b:00007ffca19c4118 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007ffca19c45b0 RCX: 00007f89fe111b0a
RDX: 00007ffca19c4120 RSI: 00007ffca19c45b0 RDI: 00000000ffffff9c
RBP: 000056073e4a02c0 R08: 0000000000000000 R09: 0000000000000020
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffca19c41b0
R13: 00007ffca19c49e5 R14: 00005607064daca4 R15: 00005607064dabcc
rcu: rcu_preempt kthread starved for 4156 jiffies! g45833 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:28680 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7004
schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 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: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 96 6c 52 f6 48 89 df e8 7e bc 52 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 15 f3 42 f6 65 8b 05 9e 1e 7b 08 85 c0 74 16 5b
RSP: 0018:ffffc90000a08388 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffffffff9b373538 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8de71b50 RDI: ffffffff8c1aefa0
RBP: 0000000000000286 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000050 R14: 0000000000000050 R15: ffff88819f4109c0
FS: 0000000000000000(0000) GS:ffff888124448000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555655fa4e8 CR3: 000000007983c000 CR4: 00000000003526f0
Call Trace:
__debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
debug_check_no_obj_freed+0x31f/0x630 lib/debugobjects.c:1129
slab_free_hook mm/slub.c:2618 [inline]
slab_free mm/slub.c:6124 [inline]
kmem_cache_free+0x3c8/0x6a0 mm/slub.c:6254
skb_kfree_head net/core/skbuff.c:1087 [inline]
skb_kfree_head net/core/skbuff.c:1084 [inline]
skb_free_head+0x1c6/0x220 net/core/skbuff.c:1101
skb_release_data+0x79b/0x9d0 net/core/skbuff.c:1128
skb_release_all net/core/skbuff.c:1203 [inline]
__kfree_skb net/core/skbuff.c:1217 [inline]
consume_skb net/core/skbuff.c:1450 [inline]
consume_skb+0xc4/0x110 net/core/skbuff.c:1444
nft_synproxy_eval_v4 net/netfilter/nft_synproxy.c:61 [inline]
nft_synproxy_do_eval+0xa7b/0xd50 net/netfilter/nft_synproxy.c:142
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x2e8/0x1930 net/netfilter/nf_tables_core.c:285
nft_do_chain_inet+0xee/0x340 net/netfilter/nft_chain_filter.c:161
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xbf/0x220 net/netfilter/core.c:623
nf_hook.constprop.0+0x2a6/0x750 include/linux/netfilter.h:273
NF_HOOK include/linux/netfilter.h:316 [inline]
ip_local_deliver+0x163/0x1f0 net/ipv4/ip_input.c:262
dst_input include/net/dst.h:480 [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+0x2d9/0x5d0 net/ipv4/ip_input.c:573
__netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6149
__netif_receive_skb+0x1f/0x120 net/core/dev.c:6262
process_backlog+0x37a/0x1580 net/core/dev.c:6614
__napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7678
napi_poll net/core/dev.c:7741 [inline]
net_rx_action+0xa40/0xf20 net/core/dev.c:7893
handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xef/0x150 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+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: c8 82 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 fc 1b 00 fb f4 bc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df0 EFLAGS: 00000246
RAX: 0000000003bf4ad1 RBX: ffff88801e2fa480 RCX: ffffffff8b8f8c75
RDX: 0000000000000000 RSI: ffffffff8de71b50 RDI: ffffffff8c1aefa0
RBP: 0000000000000001 R08: 0000000000000001 R09: ffffed10170a6795
R10: ffff8880b8533cab R11: 0000000000000000 R12: ffffed1003c5f490
R13: 0000000000000001 R14: ffffffff90d96310 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:73 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x35b/0x4b0 kernel/sched/idle.c:332
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148