rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17405/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=136845, q=384 ncpus=2)
task:syz-executor state:R running task stack:24104 pid:17405 tgid:17405 ppid:5834 task_flags:0x40050c flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288
irqentry_exit+0x6f/0x90 kernel/entry/common.c:197
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:100 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
RIP: 0010:unwind_next_frame+0x12dc/0x2390 arch/x86/kernel/unwind_orc.c:494
Code: 3e b0 00 48 8b 44 24 18 48 8b 10 48 c7 c7 a0 3c 88 8b 89 de e8 e5 c7 b4 ff e9 43 06 00 00 49 89 d5 48 89 d5 48 89 d8 48 29 e8 <48> 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe 4c 8d 3c 45
RSP: 0018:ffffc90003df7038 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff8fbdb4c8 RCX: 4f2c297e950c7c00
RDX: ffffffff8fbdb4c8 RSI: ffffffff903d4322 RDI: ffffffff8be340a0
RBP: ffffffff8fbdb4c8 R08: 0000000000000001 R09: ffffffff8172c195
R10: ffffc90003df7158 R11: ffffffff81ac4020 R12: ffffffff820ddcce
R13: ffffffff8fbdb4c8 R14: ffffc90003df7108 R15: 0000000000010ddc
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
unpoison_slab_object mm/kasan/common.c:330 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4180 [inline]
slab_alloc_node mm/slub.c:4229 [inline]
kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236
kmem_alloc_batch lib/debugobjects.c:371 [inline]
fill_pool+0x100/0x570 lib/debugobjects.c:403
debug_objects_fill_pool lib/debugobjects.c:725 [inline]
debug_object_activate+0x383/0x420 lib/debugobjects.c:814
debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
__call_rcu_common kernel/rcu/tree.c:3108 [inline]
call_rcu+0xaa/0x9c0 kernel/rcu/tree.c:3243
slab_free_hook mm/slub.c:2381 [inline]
slab_free mm/slub.c:4680 [inline]
kmem_cache_free+0x309/0x400 mm/slub.c:4782
exit_mmap+0x53f/0xb50 mm/mmap.c:1305
__mmput+0x118/0x430 kernel/fork.c:1129
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
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/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5031584d93
RSP: 002b:00007ffdd902edc8 EFLAGS: 00000202 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 000000000000440e RCX: 00007f5031584d93
RDX: 0000000040000000 RSI: 00007ffdd902eddc RDI: 00000000ffffffff
RBP: 00007ffdd902eddc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 9619 jiffies! g136845 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:26792 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
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+0x70e/0x8a0 kernel/kthread.c:463
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: 0 Comm: swapper/1 Not tainted 6.16.0-next-20250731-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4877 [inline]
RIP: 0010:__lock_acquire+0x4d8/0xd20 kernel/locking/lockdep.c:5187
Code: 0f 84 d7 04 00 00 44 3b bf e8 0a 00 00 0f 8d 04 01 00 00 49 63 df 48 8d 04 9b 4c 8d 3c c7 49 81 c7 10 0b 00 00 eb 1d 44 89 e0 <48> ff c3 48 63 8f e8 0a 00 00 49 83 c7 28 41 89 c4 48 39 cb 0f 8d
RSP: 0018:ffffc90000a076c8 EFLAGS: 00000093
RAX: 0000000000000003 RBX: 0000000000000000 RCX: ffffffff934698a8
RDX: 0000000000000003 RSI: 0000000000000003 RDI: ffff88801cebda00
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8172c195
R10: ffffc90000a07918 R11: ffffffff81ac4020 R12: ffffffffffffff03
R13: 0000000000000001 R14: ffff88801cebe568 R15: ffff88801cebe510
FS: 0000000000000000(0000) GS:ffff888125d43000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3486847e5f CR3: 0000000044aaa000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
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:243 [inline]
__kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2417 [inline]
slab_free mm/slub.c:4680 [inline]
kmem_cache_free+0x18f/0x400 mm/slub.c:4782
skb_release_all net/core/skbuff.c:1149 [inline]
__kfree_skb net/core/skbuff.c:1165 [inline]
sk_skb_reason_drop+0xe9/0x170 net/core/skbuff.c:1203
kfree_skb_reason include/linux/skbuff.h:1275 [inline]
kfree_skb include/linux/skbuff.h:1284 [inline]
ip6_mc_input+0x8f4/0xaf0 net/ipv6/ip6_input.c:593
ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:993
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_slow+0xc2/0x220 net/netfilter/core.c:623
nf_hook include/linux/netfilter.h:273 [inline]
NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316
__netif_receive_skb_one_core net/core/dev.c:5979 [inline]
__netif_receive_skb+0xd3/0x380 net/core/dev.c:6092
netif_receive_skb_internal net/core/dev.c:6178 [inline]
netif_receive_skb+0x1cb/0x790 net/core/dev.c:6237
NF_HOOK+0xa0/0x390 include/linux/netfilter.h:319
br_handle_frame_finish+0x14d1/0x19b0 net/bridge/br_input.c:-1
br_nf_hook_thresh+0x3c3/0x4a0 net/bridge/br_netfilter_hooks.c:-1
br_nf_pre_routing_finish_ipv6+0x948/0xd00 net/bridge/br_netfilter_ipv6.c:-1
NF_HOOK include/linux/netfilter.h:318 [inline]
br_nf_pre_routing_ipv6+0x37e/0x6b0 net/bridge/br_netfilter_ipv6.c:184
nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
nf_hook_bridge_pre net/bridge/br_input.c:283 [inline]
br_handle_frame+0x982/0x14c0 net/bridge/br_input.c:434
__netif_receive_skb_core+0x10b9/0x4020 net/core/dev.c:5866
__netif_receive_skb_one_core net/core/dev.c:5977 [inline]
__netif_receive_skb+0x72/0x380 net/core/dev.c:6092
process_backlog+0x60e/0x14f0 net/core/dev.c:6444
__napi_poll+0xc7/0x360 net/core/dev.c:7497
napi_poll net/core/dev.c:7560 [inline]
net_rx_action+0x707/0xe30 net/core/dev.c:7687
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 53 e8 02 00 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 d3 06 11 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6
RAX: f2181734392c9d00 RBX: ffffffff81968308 RCX: f2181734392c9d00
RDX: 0000000000000001 RSI: ffffffff8d98c137 RDI: ffffffff8be34100
RBP: ffffc90000197f20 R08: ffff8880b8732f5b R09: 1ffff110170e65eb
R10: dffffc0000000000 R11: ffffed10170e65ec R12: ffffffff8fa21830
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039d7b40
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x1e8/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x147
net_ratelimit: 11224 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:46:e7:13:42:14:64, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:46:e7:13:42:14:64, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:46:e7:13:42:14:64, vlan:0)