rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5838/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=24237, q=977 ncpus=2)
task:syz-executor state:R running task stack:21856 pid:5838 tgid:5838 ppid:5832 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109
irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875
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 6b 55 fe 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:ffffc9000407f158 EFLAGS: 00000206
RAX: 2a743c9093e08d00 RBX: 0000000000000000 RCX: 2a743c9093e08d00
RDX: 0000000000000000 RSI: ffffffff8db6fcc6 RDI: ffffffff8be1ba40
RBP: ffffffff8172aae5 R08: 0000000000000000 R09: ffffffff8172aae5
R10: ffffc9000407f318 R11: ffffffff81acfd40 R12: 0000000000000002
R13: ffffffff8e13f0e0 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [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+0xf7/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1248 [inline]
__free_frozen_pages+0xc65/0xe60 mm/page_alloc.c:2706
discard_slab mm/slub.c:2717 [inline]
__put_partials+0x161/0x1c0 mm/slub.c:3186
put_cpu_partial+0x17c/0x250 mm/slub.c:3261
__slab_free+0x2f7/0x400 mm/slub.c:4513
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_slab_alloc+0x22/0x80 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4148 [inline]
slab_alloc_node mm/slub.c:4197 [inline]
kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4204
vm_area_dup+0x2b/0x680 mm/vma_init.c:122
dup_mmap+0x90c/0x1ac0 mm/mmap.c:1784
dup_mm kernel/fork.c:1477 [inline]
copy_mm+0x13c/0x4b0 kernel/fork.c:1529
copy_process+0x16d3/0x3b80 kernel/fork.c:2169
kernel_clone+0x224/0x7f0 kernel/fork.c:2599
__do_sys_clone kernel/fork.c:2742 [inline]
__se_sys_clone kernel/fork.c:2726 [inline]
__x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2726
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9f8ff85453
RSP: 002b:00007fffb8e436e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f9f8ff85453
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055558250c7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000003bca8 R15: 00007fffb8e43880
rcu: rcu_preempt kthread starved for 1489 jiffies! g24237 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:27128 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5397 [inline]
__schedule+0x16aa/0x4c90 kernel/sched/core.c:6786
__schedule_loop kernel/sched/core.c:6864 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6879
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
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: 3413 Comm: kworker/R-bat_e Not tainted 6.16.0-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: bat_events batadv_dat_purge
RIP: 0010:hlock_class kernel/locking/lockdep.c:246 [inline]
RIP: 0010:__lock_acquire+0xa51/0xd20 kernel/locking/lockdep.c:5237
Code: 90 0f 0b 90 90 90 31 c0 48 8b 3c 24 48 83 78 40 00 0f 84 8c 02 00 00 41 8b 46 20 25 ff 1f 00 00 48 0f a3 05 f1 fb 05 12 73 10 <48> 69 c0 c8 00 00 00 48 8d 80 f0 42 45 93 eb 40 83 3d 38 8b 09 18
RSP: 0018:ffffc90000a07bc8 EFLAGS: 00000003
RAX: 0000000000000007 RBX: 0000000000000005 RCX: 0000000002fcf7df
RDX: 000000004dbb4af1 RSI: 000000007f45ee1d RDI: ffff8880316a0000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8172aae5
R10: ffffc90000a07e18 R11: ffffffff81acfd40 R12: 00000000c6ada59f
R13: ffff8880316a0af0 R14: ffff8880316a0bb8 R15: 03813abc02fcf7df
FS: 0000000000000000(0000) GS:ffff888125d57000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c320412 CR3: 000000002b9fe000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [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
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2381 [inline]
slab_free mm/slub.c:4643 [inline]
kmem_cache_free+0x18f/0x400 mm/slub.c:4745
skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1087
skb_release_all net/core/skbuff.c:1152 [inline]
__kfree_skb net/core/skbuff.c:1166 [inline]
consume_skb+0x9e/0xf0 net/core/skbuff.c:1398
nft_synproxy_eval_v6+0x376/0x560 net/netfilter/nft_synproxy.c:91
nft_synproxy_do_eval+0x3d7/0x570 net/netfilter/nft_synproxy.c:145
expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]
nft_do_chain+0x409/0x1920 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:157 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:272 [inline]
NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:315
ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:491
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:317
__netif_receive_skb_one_core net/core/dev.c:5977 [inline]
__netif_receive_skb+0xd3/0x380 net/core/dev.c:6090
process_backlog+0x60e/0x14f0 net/core/dev.c:6442
__napi_poll+0xc4/0x480 net/core/dev.c:7414
napi_poll net/core/dev.c:7478 [inline]
net_rx_action+0x707/0xe30 net/core/dev.c:7605
handle_softirqs+0x283/0x870 kernel/softirq.c:579
do_softirq+0xec/0x180 kernel/softirq.c:480
__local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407
spin_unlock_bh include/linux/spinlock.h:396 [inline]
__batadv_dat_purge net/batman-adv/distributed-arp-table.c:185 [inline]
batadv_dat_purge+0x2da/0x3c0 net/batman-adv/distributed-arp-table.c:204
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
rescuer_thread+0x53c/0xdd0 kernel/workqueue.c:3498
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245