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 veth0_to_bridge with own address as source address (addr:6a:2e:f6:a9:c3:02, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6157/1:b..l rcu: (detected by 1, t=10503 jiffies, g=10653, q=2190 ncpus=2) task:syz.0.54 state:R running task stack:26760 pid:6157 tgid:6151 ppid:5844 task_flags:0x400140 flags:0x00080002 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:lock_acquire+0x5e/0x380 kernel/locking/lockdep.c:5872 Code: 05 3b 22 28 12 83 f8 07 0f 87 f0 00 00 00 48 0f a3 05 06 71 f4 0e 0f 82 c2 02 00 00 8b 35 1e a4 f4 0e 85 f6 0f 85 dd 00 00 00 <48> 8b 44 24 30 65 48 2b 05 dd 21 28 12 0f 85 02 03 00 00 48 83 c4 RSP: 0018:ffffc90004bdf6f8 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8de46ec7 RDI: ffffffff8c1adfa0 RBP: ffffffff8e7e94a0 R08: 00000000b34c138e R09: 0000000000000007 R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xd1/0x1ea0 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 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4459 [inline] kmem_cache_alloc_bulk_noprof+0x39b/0x950 mm/slub.c:7204 __io_alloc_req_refill+0x9e/0x330 io_uring/io_uring.c:965 io_alloc_req io_uring/io_uring.h:508 [inline] io_submit_sqes.cold+0x264/0x2cb io_uring/io_uring.c:2032 __do_sys_io_uring_enter+0x9c0/0x1a20 io_uring/io_uring.c:2603 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: 0033:0x7fa73299bf79 RSP: 002b:00007fa733845028 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007fa732c16180 RCX: 00007fa73299bf79 RDX: 00000000000004c1 RSI: 0000000000000627 RDI: 0000000000000006 RBP: 00007fa732a327e0 R08: 0000000000000000 R09: 0000000000000030 R10: 0000000000000043 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa732c16218 R14: 00007fa732c16180 R15: 00007ffd5e062e08 rcu: rcu_preempt kthread starved for 6559 jiffies! g10653 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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: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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:lock_is_held_type+0xf9/0x140 kernel/locking/lockdep.c:5945 Code: 65 0f c1 15 91 e8 7e 08 83 fa 01 8b 44 24 04 75 2d 9c 5a 80 e6 02 75 47 41 f7 c5 00 02 00 00 74 01 fb 48 83 c4 08 5b 5d 41 5c <41> 5d 41 5e 41 5f e9 7c 2c 03 00 c3 cc cc cc cc 31 c0 eb ad 90 0f RSP: 0018:ffffc90000006bf8 EFLAGS: 00000292 RAX: 0000000000000001 RBX: 00000000000a88ac RCX: 0000000000000001 RDX: 0000000000000046 RSI: ffffffff8de46ec7 RDI: ffffffff8c1adfa0 RBP: ffff88801d780000 R08: 0000000000000006 R09: 0000000000001000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004 R13: 0000000000000246 R14: ffffffff8e4980d8 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124352000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f67598f00e2 CR3: 000000002d54c000 CR4: 00000000003526f0 Call Trace: lookup_page_ext+0x6e/0x100 mm/page_ext.c:258 page_ext_iter_begin include/linux/page_ext.h:133 [inline] __page_table_check_zero+0xe1/0x410 mm/page_table_check.c:139 page_table_check_alloc include/linux/page_table_check.h:38 [inline] post_alloc_hook+0x140/0x170 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1896 [inline] get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3961 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5249 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2485 alloc_slab_page mm/slub.c:3236 [inline] allocate_slab mm/slub.c:3411 [inline] new_slab+0x44a/0x6e0 mm/slub.c:3469 ___slab_alloc+0x31b/0x8d0 mm/slub.c:4334 __slab_alloc_node mm/slub.c:4400 [inline] slab_alloc_node mm/slub.c:4776 [inline] kmem_cache_alloc_node_noprof+0x349/0x6f0 mm/slub.c:4840 kmalloc_reserve+0x148/0x350 net/core/skbuff.c:613 __alloc_skb+0x185/0x710 net/core/skbuff.c:713 alloc_skb include/linux/skbuff.h:1383 [inline] nlmsg_new include/net/netlink.h:1055 [inline] fdb_notify+0xa2/0x190 net/bridge/br_fdb.c:188 br_fdb_update+0x324/0x720 net/bridge/br_fdb.c:1040 br_handle_frame_finish+0xc75/0x1f00 net/bridge/br_input.c:144 br_nf_hook_thresh+0x30d/0x420 net/bridge/br_netfilter_hooks.c:1167 br_nf_pre_routing_finish_ipv6+0x769/0xfb0 net/bridge/br_netfilter_ipv6.c:154 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x39c/0x8b0 net/bridge/br_netfilter_ipv6.c:184 br_nf_pre_routing+0x93b/0x1510 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0xcdd/0x1520 net/bridge/br_input.c:442 __netif_receive_skb_core.constprop.0+0x6c5/0x3550 net/core/dev.c:6036 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6147 __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: a8 83 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 3c 1d 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:ffffffff8e407e00 EFLAGS: 00000246 RAX: 0000000000eb331d RBX: ffffffff8e4975c0 RCX: ffffffff8b8e4c75 RDX: 0000000000000000 RSI: ffffffff8de6ce9d RDI: ffffffff8c1adfa0 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1017086795 R10: ffff8880b8433cab R11: 0000000000000000 R12: fffffbfff1c92eb8 R13: 0000000000000000 R14: ffffffff90d92f10 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 rest_init+0x251/0x260 init/main.c:760 start_kernel+0x47f/0x480 init/main.c:1210 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x148 net_ratelimit: 17499 callbacks suppressed 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, 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 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:6a:2e:f6:a9:c3:02, 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 bridge_slave_0 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:6a:2e:f6:a9:c3:02, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) net_ratelimit: 25159 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:6a:2e:f6:a9:c3:02, 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 bridge_slave_0 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:6a:2e:f6:a9:c3:02, 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:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:6a:2e:f6:a9:c3:02, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)