rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P16253/1:b..l P5490/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=82249, q=2164 ncpus=2)
task:dhcpcd state:R running task stack:23552 pid:5490 tgid:5490 ppid:1 task_flags:0x400140 flags:0x00080001
Call Trace:
context_switch kernel/sched/core.c:5254 [inline]
__schedule+0x17c4/0x4d60 kernel/sched/core.c:6862
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7189
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:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 db 6a f4 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc900039cf518 EFLAGS: 00000206
RAX: 4c9a0bcf091f0200 RBX: 0000000000000000 RCX: 4c9a0bcf091f0200
RDX: 0000000000000000 RSI: ffffffff8da159c5 RDI: ffffffff8bc07ce0
RBP: ffffffff8173df15 R08: 0000000000000000 R09: ffffffff8173df15
R10: ffffc900039cf6d8 R11: ffffffff81ac9fd0 R12: 0000000000000002
R13: ffffffff8e13d720 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
__free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2951
discard_slab mm/slub.c:3317 [inline]
__put_partials+0x146/0x170 mm/slub.c:3864
put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3939
__slab_free+0x2b9/0x390 mm/slub.c:5913
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:405
kasan_kmalloc include/linux/kasan.h:262 [inline]
__kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5755
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
task_numa_work+0x917/0x1580 kernel/sched/fair.c:3412
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd9ac272378
RSP: 002b:00007ffc664d2218 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 000056067122e980 RCX: 00007fd9ac272378
RDX: 00007ffc664d2220 RSI: 0000000000008921 RDI: 000000000000000f
RBP: 00007ffc664d2220 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000560670ffab60
R13: 000056067122e980 R14: 0000560670ffab60 R15: 00007ffc664d2470
task:kworker/u8:11 state:R running task stack:22280 pid:16253 tgid:16253 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: iou_exit io_ring_exit_work
Call Trace:
context_switch kernel/sched/core.c:5254 [inline]
__schedule+0x17c4/0x4d60 kernel/sched/core.c:6862
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7189
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:unwind_next_frame+0x173c/0x2390 arch/x86/kernel/unwind_orc.c:648
Code: e8 89 0c 00 00 e9 f7 01 00 00 48 8b 54 24 08 48 8d 5a 02 48 83 c2 03 48 89 d8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 19 0b 00 00 <48> 89 d0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 2b 0b 00 00 48 0f bf
RSP: 0018:ffffc9000e597318 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff9031191e RCX: 0000000000000000
RDX: ffffffff9031191f RSI: 0000000000000001 RDI: ffffc9000e597448
RBP: dffffc0000000000 R08: ffffc9000e597447 R09: 0000000000000000
R10: ffffc9000e597438 R11: fffff52001cb2e89 R12: ffffc9000e597520
R13: ffffc9000e597438 R14: ffffc9000e5973e8 R15: 1ffffffff2062324
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414
kasan_kmalloc include/linux/kasan.h:262 [inline]
__kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5755
kmalloc_noprof include/linux/slab.h:957 [inline]
slab_free_hook mm/slub.c:2482 [inline]
slab_free mm/slub.c:6619 [inline]
kmem_cache_free+0x16f/0x690 mm/slub.c:6729
__io_req_caches_free+0x1c1/0x270 io_uring/io_uring.c:2837
io_req_caches_free+0x21/0x60 io_uring/io_uring.c:2849
io_ring_exit_work+0x415/0x930 io_uring/io_uring.c:3047
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
rcu: rcu_preempt kthread starved for 5846 jiffies! g82249 f0x0 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:27520 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5254 [inline]
__schedule+0x17c4/0x4d60 kernel/sched/core.c:6862
__schedule_loop kernel/sched/core.c:6944 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6959
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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:rcu_is_watching+0x70/0xb0 kernel/rcu/tree.c:753
Code: c3 d8 5f 93 92 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 34 8b 03 65 ff 0d f9 6e eb 10 74 11 83 e0 04 c1 e8 02 5b <41> 5e 41 5f e9 57 e4 aa 09 cc e8 11 b7 8c ff eb e8 48 c7 c7 00 34
RSP: 0018:ffffc90000a07678 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff90b73f01 RCX: 723faa56fd6b4c00
RDX: ffffc90000a07801 RSI: ffffffff8bc07cc0 RDI: ffffffff8bc07c80
RBP: dffffc0000000000 R08: ffffc90000a08670 R09: 0000000000000000
R10: ffffc90000a07818 R11: fffff52000140f05 R12: ffffc90000a08680
R13: ffffffff8173df15 R14: ffffffff8da4edd8 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888125dfd000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc1ae35c78 CR3: 000000007483a000 CR4: 00000000003526f0
Call Trace:
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x4b/0x3e0 kernel/locking/lockdep.c:5879
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:897 [inline]
class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0x19a9/0x2390 arch/x86/kernel/unwind_orc.c:680
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:165
__set_page_owner+0x8d/0x4c0 mm/page_owner.c:341
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850
prep_new_page mm/page_alloc.c:1858 [inline]
get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3934
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5233
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2418
alloc_slab_page mm/slub.c:3046 [inline]
allocate_slab+0x96/0x3a0 mm/slub.c:3219
new_slab mm/slub.c:3273 [inline]
___slab_alloc+0xe94/0x18a0 mm/slub.c:4643
__slab_alloc+0x65/0x100 mm/slub.c:4762
__slab_alloc_node mm/slub.c:4838 [inline]
slab_alloc_node mm/slub.c:5260 [inline]
kmem_cache_alloc_node_noprof+0x4ce/0x710 mm/slub.c:5324
__alloc_skb+0x112/0x2d0 net/core/skbuff.c:660
alloc_skb include/linux/skbuff.h:1383 [inline]
synproxy_send_client_synack+0x16c/0xe20 net/netfilter/nf_synproxy_core.c:460
nft_synproxy_eval_v4+0x36e/0x560 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x345/0x570 net/netfilter/nft_synproxy.c:141
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
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6119 [inline]
__netif_receive_skb+0x143/0x380 net/core/dev.c:6232
process_backlog+0x60e/0x14f0 net/core/dev.c:6584
__napi_poll+0xc7/0x360 net/core/dev.c:7634
napi_poll net/core/dev.c:7697 [inline]
net_rx_action+0x5f7/0xdf0 net/core/dev.c:7824
handle_softirqs+0x286/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 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 33 76 19 00 f3 0f 1e fa fb f4 c8 e7 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6
RAX: 723faa56fd6b4c00 RBX: ffffffff8196ec67 RCX: 723faa56fd6b4c00
RDX: 0000000000000001 RSI: ffffffff8d82c798 RDI: ffffffff8bc07ce0
RBP: ffffc90000197f10 R08: ffff8880b8732fdb R09: 1ffff110170e65fb
R10: dffffc0000000000 R11: ffffed10170e65fc R12: ffffffff8f9e3570
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003a54b58
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e7/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147