rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: (detected by 0, t=10502 jiffies, g=79509, q=1074 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 3459 (4295024285-4295020826), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 3460 jiffies! g79509 f0x2 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:27496 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5526 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7277
__schedule_loop kernel/sched/core.c:7354 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7369
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 3194 Comm: kworker/R-ipv6_ Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:unwind_get_return_address+0x67/0x90 arch/x86/kernel/unwind_orc.c:386
Code: 48 89 df e8 1b ea bf 00 48 8b 3b e8 d3 e1 18 00 85 c0 74 14 43 80 3c 37 00 74 08 48 89 df e8 00 ea bf 00 48 8b 03 eb 02 31 c0 <5b> 41 5e 41 5f c3 cc cc cc cc cc 89 d9 80 e1 07 80 c1 03 38 c1 7c
RSP: 0018:ffffc90000006c88 EFLAGS: 00000246
RAX: ffffffff8237a8d2 RBX: ffffc90000006cf0 RCX: 8000000000000100
RDX: ffffffff91208401 RSI: ffffffff8e69c835 RDI: ffffffff8237a8d2
RBP: ffffc90000006d30 R08: ffffc9000de1f840 R09: 0000000000000000
R10: ffffc90000006cf8 R11: fffff52000000da1 R12: ffff8880321d0000
R13: ffffffff822befa6 R14: dffffc0000000000 R15: 1ffff92000000d9e
FS: 0000000000000000(0000) GS:ffff888124cce000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fadc5400000 CR3: 000000007e878000 CR4: 00000000003526f0
Call Trace:
arch_stack_walk+0xfb/0x150 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4683 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
kmem_cache_alloc_noprof+0x2b9/0x600 mm/slub.c:5010
skb_ext_maybe_cow net/core/skbuff.c:7167 [inline]
skb_ext_add+0x1b6/0x8e0 net/core/skbuff.c:7242
nf_bridge_unshare net/bridge/br_netfilter_hooks.c:170 [inline]
br_nf_forward_ip+0xc3/0xa30 net/bridge/br_netfilter_hooks.c:686
nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
nf_hook include/linux/netfilter.h:280 [inline]
NF_HOOK+0x23e/0x3f0 include/linux/netfilter.h:323
__br_forward+0x397/0x540 net/bridge/br_forward.c:115
deliver_clone net/bridge/br_forward.c:131 [inline]
maybe_deliver net/bridge/br_forward.c:191 [inline]
br_flood+0x3e3/0x8d0 net/bridge/br_forward.c:245
br_handle_frame_finish+0x1119/0x1950 net/bridge/br_input.c:229
br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1
br_nf_pre_routing_finish_ipv6+0x90c/0xc40 net/bridge/br_netfilter_ipv6.c:-1
NF_HOOK include/linux/netfilter.h:325 [inline]
br_nf_pre_routing_ipv6+0x382/0x6f0 net/bridge/br_netfilter_ipv6.c:183
nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
br_handle_frame+0x1329/0x1600 net/bridge/br_input.c:451
__netif_receive_skb_core+0x989/0x30c0 net/core/dev.c:6151
__netif_receive_skb_one_core net/core/dev.c:6262 [inline]
__netif_receive_skb net/core/dev.c:6377 [inline]
process_backlog+0x727/0x18b0 net/core/dev.c:6728
__napi_poll+0xaa/0x330 net/core/dev.c:7787
napi_poll net/core/dev.c:7850 [inline]
net_rx_action+0x61d/0xf50 net/core/dev.c:8007
handle_softirqs+0x226/0x860 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0xcb/0x220 kernel/softirq.c:758
irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:stack_trace_consume_entry+0x9/0x280 kernel/stacktrace.c:83
Code: 0a cc e8 fa 28 33 0a 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 <41> 55 41 54 53 48 83 ec 18 48 ba 00 00 00 00 00 fc ff df 4c 8d 47
RSP: 0018:ffffc9000de1f3e8 EFLAGS: 00000282
RAX: ffffffff816cc594 RBX: ffffc9000de1f4c0 RCX: 0000000000000000
RDX: ffffc9000de1f401 RSI: ffffffff816cc594 RDI: ffffc9000de1f4c0
RBP: ffffc9000de1f490 R08: ffffc9000de1fe70 R09: 0000000000000000
R10: ffffc9000de1f458 R11: ffffffff81b28ab0 R12: ffff8880321d0000
R13: 1ffff1100643a0bf R14: ffffffff81b28ab0 R15: ffffc9000de1f408
arch_stack_walk+0x10f/0x150 arch/x86/kernel/stacktrace.c:27
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:183
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:338
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0xc93/0xd90 mm/page_alloc.c:2962
__slab_free+0x274/0x2c0 mm/slub.c:5823
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:406
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x321/0x600 mm/slub.c:5563
_kmalloc_noprof include/linux/slab.h:991 [inline]
_kzalloc_noprof include/linux/slab.h:1312 [inline]
mca_alloc net/ipv6/mcast.c:890 [inline]
__ipv6_dev_mc_inc+0x447/0xaf0 net/ipv6/mcast.c:981
addrconf_join_solict net/ipv6/addrconf.c:2262 [inline]
addrconf_dad_begin net/ipv6/addrconf.c:4135 [inline]
addrconf_dad_work+0x3fc/0x15c0 net/ipv6/addrconf.c:4263
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
rescuer_thread+0x7c5/0x10e0 kernel/workqueue.c:3703
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245