bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5770/1:b..l rcu: (detected by 0, t=10502 jiffies, g=13645, q=687 ncpus=2) task:syz-executor state:R running task stack:24360 pid:5770 ppid:5761 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6868 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6892 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3a/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] zap_pte_range mm/memory.c:1523 [inline] zap_pmd_range mm/memory.c:1571 [inline] zap_pud_range mm/memory.c:1600 [inline] zap_p4d_range mm/memory.c:1621 [inline] unmap_page_range+0x2577/0x32f0 mm/memory.c:1642 unmap_vmas+0x286/0x3f0 mm/memory.c:1732 exit_mmap+0x238/0xb90 mm/mmap.c:3302 __mmput+0x118/0x3a0 kernel/fork.c:1362 exit_mm+0x23f/0x340 kernel/exit.c:576 do_exit+0x909/0x2530 kernel/exit.c:877 do_group_exit+0x22d/0x2f0 kernel/exit.c:1032 get_signal+0x12a6/0x1390 kernel/signal.c:2915 arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:213 __syscall_exit_to_user_mode_work kernel/entry/common.c:294 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:305 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f58f07596d7 RSP: 002b:00007fff4dccb6e0 EFLAGS: 00000202 ORIG_RAX: 000000000000003d RAX: fffffffffffffe00 RBX: 00005555844b8500 RCX: 00007f58f07596d7 RDX: 0000000040000000 RSI: 00007fff4dccb73c RDI: ffffffffffffffff RBP: 00007fff4dccb73c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 R13: 0000000000000003 R14: 00007fff4dccb998 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 926 jiffies! g13645 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:27848 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 6639 Comm: syz.2.260 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 RIP: 0010:check_kcov_mode kernel/kcov.c:178 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x2e/0x60 kernel/kcov.c:212 Code: 48 8b 04 24 65 48 8b 0d 40 27 7c 7e 65 8b 15 41 27 7c 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 24 16 00 00 00 <74> 2c 8b 91 00 16 00 00 83 fa 02 75 21 48 8b 91 08 16 00 00 48 8b RSP: 0018:ffffc90000006ab8 EFLAGS: 00000246 RAX: ffffffff813bb2a1 RBX: ffffc90000006b30 RCX: ffff88802e56da00 RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffff88802e56da00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000100 R12: ffffffff88880284 R13: 00000000000000b8 R14: dffffc0000000000 R15: 1ffff92000000d66 FS: 00007fe2ec7836c0(0000) GS:ffff8880b8c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f673b8cffb3 CR3: 0000000031bc1000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: unwind_get_return_address+0x71/0xc0 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0x11d/0x190 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:770 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x17e/0x2c0 mm/slub.c:3519 skb_ext_maybe_cow net/core/skbuff.c:6709 [inline] skb_ext_add+0x1b3/0x8e0 net/core/skbuff.c:6783 nf_bridge_unshare net/bridge/br_netfilter_hooks.c:165 [inline] br_nf_forward_ip+0xc6/0x10d0 net/bridge/br_netfilter_hooks.c:713 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline] nf_hook_slow+0xbd/0x200 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:259 [inline] NF_HOOK+0x23e/0x3e0 include/linux/netfilter.h:302 __br_forward+0x433/0x610 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver+0xb5/0x150 net/bridge/br_forward.c:191 br_flood+0x317/0x670 net/bridge/br_forward.c:237 br_handle_frame_finish+0xf2d/0x15c0 net/bridge/br_input.c:215 br_nf_hook_thresh+0x3cd/0x4a0 net/bridge/br_netfilter_hooks.c:1188 br_nf_pre_routing_finish_ipv6+0x9e5/0xd20 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:304 [inline] br_nf_pre_routing_ipv6+0x34d/0x6a0 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x1240/0x14d0 net/bridge/br_input.c:424 __netif_receive_skb_core+0xf94/0x3ac0 net/core/dev.c:5565 __netif_receive_skb_one_core net/core/dev.c:5669 [inline] __netif_receive_skb+0x74/0x290 net/core/dev.c:5785 process_backlog+0x380/0x710 net/core/dev.c:6113 __napi_poll+0xbb/0x460 net/core/dev.c:6675 napi_poll net/core/dev.c:6742 [inline] net_rx_action+0x65f/0xcc0 net/core/dev.c:6878 handle_softirqs+0x27d/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xc0/0x120 kernel/locking/spinlock.c:194 Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 ab 35 c0 f6 65 8b 05 1c f3 66 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc90003927580 EFLAGS: 00000206 RAX: dffffc0000000004 RBX: 0000000000000a02 RCX: b29ddcd8f3b08400 RDX: dffffc0000000000 RSI: ffffffff8acacfe0 RDI: 0000000000000001 RBP: ffffc90003927610 R08: ffffffff91ff152f R09: 1ffffffff23fe2a5 R10: dffffc0000000000 R11: fffffbfff23fe2a6 R12: dffffc0000000000 R13: ffff88806c198000 R14: ffffffff983032b0 R15: 1ffff92000724eb0 __debug_check_no_obj_freed lib/debugobjects.c:1054 [inline] debug_check_no_obj_freed+0x47b/0x520 lib/debugobjects.c:1075 free_pages_prepare mm/page_alloc.c:1188 [inline] free_unref_page_prepare+0x1ed/0x8f0 mm/page_alloc.c:2366 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459 discard_slab mm/slub.c:2127 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667 put_cpu_partial+0x17c/0x250 mm/slub.c:2743 __slab_free+0x319/0x400 mm/slub.c:3700 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:770 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x17e/0x2c0 mm/slub.c:3519 kmem_cache_zalloc include/linux/slab.h:711 [inline] taskstats_tgid_alloc kernel/taskstats.c:585 [inline] taskstats_exit+0x14d/0xce0 kernel/taskstats.c:624 do_exit+0x8fc/0x2530 kernel/exit.c:866 do_group_exit+0x22d/0x2f0 kernel/exit.c:1032 get_signal+0x12a6/0x1390 kernel/signal.c:2915 arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:213 __syscall_exit_to_user_mode_work kernel/entry/common.c:294 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:305 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fe2eb99e559 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe2ec7830e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007fe2ebc26098 RCX: 00007fe2eb99e559 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fe2ebc26098 RBP: 00007fe2ebc26090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fe2ebc26128 R14: 00007fffb99977f0 R15: 00007fffb99978d8 net_ratelimit: 4207 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 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: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 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 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: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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)