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:ba:b2:df:f6:3c:d5, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5805/1:b..l rcu: (detected by 1, t=10502 jiffies, g=40897, q=140 ncpus=2) task:syz-executor state:R running task stack:24232 pid:5805 ppid:5798 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891 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+0x2315/0x3000 mm/memory.c:1642 unmap_vmas+0x286/0x3f0 mm/memory.c:1732 exit_mmap+0x238/0xb90 mm/mmap.c:3302 __mmput+0x118/0x3c0 kernel/fork.c:1355 exit_mm+0x1f2/0x2c0 kernel/exit.c:569 do_exit+0x8dd/0x2460 kernel/exit.c:870 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 get_signal+0x12fc/0x13f0 kernel/signal.c:2902 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fc2e8755ed7 RSP: 002b:00007fff0607c150 EFLAGS: 00000202 ORIG_RAX: 000000000000003d RAX: fffffffffffffe00 RBX: 00005555771db500 RCX: 00007fc2e8755ed7 RDX: 0000000040000000 RSI: 00007fff0607c1ac RDI: ffffffffffffffff RBP: 00007fff0607c1ac R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 R13: 0000000000000003 R14: 00007fff0607c408 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 967 jiffies! g40897 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:26952 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1553/0x45a0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x313/0x1590 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: 1 PID: 10828 Comm: syz.3.1686 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__sanitizer_cov_trace_const_cmp2+0x4/0x90 kernel/kcov.c:307 Code: 48 c7 44 11 08 01 00 00 00 48 89 7c 11 10 48 89 74 11 18 48 89 44 11 20 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa <48> 8b 04 24 65 48 8b 15 70 9f 7c 7e 65 8b 0d 71 9f 7c 7e 81 e1 00 RSP: 0018:ffffc900001ef7d8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff9200003df08 RCX: 0000000000000100 RDX: ffff88802a469e00 RSI: 0000000000000038 RDI: 000000000000ffff RBP: ffffc900001ef930 R08: ffffc900001ef887 R09: 0000000000000000 R10: ffffc900001ef860 R11: fffff5200003df11 R12: 0000000000000038 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88804c9f7ab6 FS: 00007f961ca976c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4247b4da08 CR3: 000000006b5b3000 CR4: 00000000003506e0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: skb_transport_header_was_set include/linux/skbuff.h:2866 [inline] skb_transport_header include/linux/skbuff.h:2871 [inline] skb_transport_offset include/linux/skbuff.h:3018 [inline] ip6_multipath_l3_keys+0x32f/0x6d0 net/ipv6/route.c:2355 rt6_multipath_hash+0x3ce/0x1550 net/ipv6/route.c:2516 ip6_route_input+0x895/0xa50 net/ipv6/route.c:2630 ip6_rcv_finish+0x143/0x230 net/ipv6/ip6_input.c:77 ip_sabotage_in+0x1f4/0x280 net/bridge/br_netfilter_hooks.c:1001 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+0x21d/0x3b0 include/linux/netfilter.h:302 __netif_receive_skb_one_core net/core/dev.c:5638 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5752 netif_receive_skb_internal net/core/dev.c:5838 [inline] netif_receive_skb+0x1bc/0x720 net/core/dev.c:5897 NF_HOOK+0x9e/0x3a0 include/linux/netfilter.h:304 br_handle_frame_finish+0x14b9/0x19b0 net/bridge/br_input.c:221 br_nf_hook_thresh+0x3cd/0x4a0 net/bridge/br_netfilter_hooks.c:1184 br_nf_pre_routing_finish_ipv6+0x9dc/0xd00 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:304 [inline] br_nf_pre_routing_ipv6+0x349/0x6b0 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+0x96b/0x14e0 net/bridge/br_input.c:424 __netif_receive_skb_core+0xfab/0x3af0 net/core/dev.c:5532 __netif_receive_skb_one_core net/core/dev.c:5636 [inline] __netif_receive_skb+0x74/0x290 net/core/dev.c:5752 process_backlog+0x396/0x700 net/core/dev.c:6080 __napi_poll+0xc0/0x460 net/core/dev.c:6642 napi_poll net/core/dev.c:6709 [inline] net_rx_action+0x616/0xc50 net/core/dev.c:6846 handle_softirqs+0x280/0x820 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:check_preemption_disabled+0x4b/0x110 lib/smp_processor_id.c:55 Code: 0d d2 94 7f 75 f7 c1 ff ff ff 7f 74 1f 65 48 8b 0c 25 28 00 00 00 48 3b 4c 24 08 0f 85 c4 00 00 00 48 83 c4 10 5b 41 5e 41 5f <5d> c3 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 74 RSP: 0018:ffffc90011fb7110 EFLAGS: 00000282 RAX: 0000000000000001 RBX: 0000000000000000 RCX: a9a0d3539be45500 RDX: 0000000000000000 RSI: ffffffff8b1c80c0 RDI: ffffffff8b1c8080 RBP: ffffc90011fb7250 R08: ffffffff8e8ad9ef R09: 1ffffffff1d15b3d R10: dffffc0000000000 R11: fffffbfff1d15b3e R12: 1ffff920023f6e34 R13: ffffffff8d131fe0 R14: 0000000000000001 R15: dffffc0000000000 rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:700 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0xc6/0x420 kernel/locking/lockdep.c:5725 rcu_lock_acquire include/linux/rcupdate.h:334 [inline] rcu_read_lock include/linux/rcupdate.h:786 [inline] page_ext_get+0x3e/0x2b0 mm/page_ext.c:508 page_table_check_clear+0x4a/0x6a0 mm/page_table_check.c:74 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline] zap_pte_range mm/memory.c:1429 [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+0x1ad9/0x3000 mm/memory.c:1642 unmap_vmas+0x286/0x3f0 mm/memory.c:1732 exit_mmap+0x238/0xb90 mm/mmap.c:3302 __mmput+0x118/0x3c0 kernel/fork.c:1355 mmput kernel/fork.c:1377 [inline] dup_mm kernel/fork.c:1708 [inline] copy_mm+0x19c3/0x1d50 kernel/fork.c:1741 copy_process+0x16f7/0x3d80 kernel/fork.c:2506 kernel_clone+0x24b/0x8a0 kernel/fork.c:2914 __do_sys_clone kernel/fork.c:3057 [inline] __se_sys_clone kernel/fork.c:3041 [inline] __x64_sys_clone+0x1b7/0x230 kernel/fork.c:3041 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f961bb9acb9 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:00007f961ca96fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f961be15fa0 RCX: 00007f961bb9acb9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f961bc08bf7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f961be16038 R14: 00007f961be15fa0 R15: 00007fff19662618 net_ratelimit: 61 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 veth0_to_bridge with own address as source address (addr:ba:b2:df:f6:3c:d5, 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 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:ba:b2:df:f6:3c:d5, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) net_ratelimit: 7487 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 veth0_to_bridge with own address as source address (addr:ba:b2:df:f6:3c:d5, 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 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:ba:b2:df:f6:3c:d5, 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 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:ba:b2:df:f6:3c:d5, vlan:0)