bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5621/1:b..l rcu: (detected by 1, t=10503 jiffies, g=26153, q=1139 ncpus=2) task:syz-executor state:R running task stack:21952 pid:5621 tgid:5621 ppid:5615 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7413 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline] _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:190 spin_unlock include/linux/spinlock.h:390 [inline] copy_pte_range mm/memory.c:1347 [inline] copy_pmd_range+0x4e08/0x5880 mm/memory.c:1408 copy_pud_range mm/memory.c:1445 [inline] copy_p4d_range mm/memory.c:1469 [inline] copy_page_range+0xc26/0x1250 mm/memory.c:1555 dup_mmap+0xf21/0x1d90 mm/mmap.c:1840 dup_mm kernel/fork.c:1538 [inline] copy_mm+0x11a/0x480 kernel/fork.c:1590 copy_process+0x1e99/0x43f0 kernel/fork.c:2288 kernel_clone+0x2d7/0x940 kernel/fork.c:2747 __do_sys_clone kernel/fork.c:2888 [inline] __se_sys_clone kernel/fork.c:2872 [inline] __x64_sys_clone+0x1b6/0x230 kernel/fork.c:2872 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc62dfc58d2 RSP: 002b:00007ffc1ad529f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007ffc1ad529f0 RCX: 00007fc62dfc58d2 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007ffc1ad52b7c R08: 0000000000000000 R09: 0000000000000001 R10: 00005555757e07d0 R11: 0000000000000246 R12: 0000000000000001 R13: 00000000000927c0 R14: 0000000000022912 R15: 00007ffc1ad52bd0 rcu: rcu_preempt kthread starved for 1067 jiffies! g26153 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:26848 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 7986 Comm: syz.3.612 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:find_held_lock kernel/locking/lockdep.c:-1 [inline] RIP: 0010:__lock_release kernel/locking/lockdep.c:5535 [inline] RIP: 0010:lock_release+0x111/0x3c0 kernel/locking/lockdep.c:5889 Code: 24 83 f8 32 0f 83 2a 02 00 00 4a 8d 1c ad 00 00 00 00 4c 01 eb 48 8d 6c dd 00 48 89 ef 4c 89 f6 e8 44 55 11 0a 44 89 64 24 14 <45> 89 e5 85 c0 0f 84 d7 00 00 00 48 85 ed 0f 84 13 01 00 00 83 7d RSP: 0018:ffffc90000006670 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000023 RCX: 0000000080010101 RDX: 0000000000010100 RSI: ffffffff8e959c20 RDI: ffff88802ae38cb8 RBP: ffff88802ae38cb8 R08: ffff88803557219f R09: 1ffff11006aae433 R10: dffffc0000000000 R11: ffffed1006aae434 R12: 0000000000000007 R13: 0000000000000007 R14: ffffffff8e959c20 R15: ffff88802ae38000 FS: 0000000000000000(0000) GS:ffff888125226000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcb93a0d40 CR3: 0000000031b90000 CR4: 00000000003526f0 Call Trace: rcu_lock_release include/linux/rcupdate.h:310 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] advance_sched+0xb13/0xc80 net/sched/sch_taprio.c:994 __run_hrtimer kernel/time/hrtimer.c:2032 [inline] __hrtimer_run_queues+0x3bc/0xa10 kernel/time/hrtimer.c:2096 hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:lock_acquire+0x221/0x350 kernel/locking/lockdep.c:5872 Code: ff ff ff e8 81 80 11 0a f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 6b 7b 9d 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 90 80 14 0a cc 48 8d 3d b8 3b 94 RSP: 0018:ffffc90000006a80 EFLAGS: 00000282 RAX: 4caec881c6fc7b00 RBX: 0000000000000000 RCX: 0000000080000101 RDX: 000000007f45ee1d RSI: ffffffff8e25a5b4 RDI: ffffffff8c2a9f80 RBP: ffffffff8176f21f R08: ffffffff8176f21f R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8e959c20 R12: 0000000000000002 R13: ffffffff8e959c20 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:840 [inline] class_rcu_constructor include/linux/rcupdate.h:1183 [inline] unwind_next_frame+0xac/0x2550 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2705 [inline] slab_free mm/slub.c:6405 [inline] kmem_cache_free+0x182/0x650 mm/slub.c:6532 kfree_skb_reason include/linux/skbuff.h:1323 [inline] kfree_skb include/linux/skbuff.h:1332 [inline] ip6_mc_input+0x909/0xbc0 net/ipv6/ip6_input.c:638 ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:988 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:316 __netif_receive_skb_one_core net/core/dev.c:6206 [inline] __netif_receive_skb net/core/dev.c:6319 [inline] netif_receive_skb_internal net/core/dev.c:6405 [inline] netif_receive_skb+0x278/0xbf0 net/core/dev.c:6464 NF_HOOK+0xa4/0x3a0 include/linux/netfilter.h:318 br_handle_frame_finish+0x1192/0x1990 net/bridge/br_input.c:-1 br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x90c/0xc40 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x382/0x6f0 net/bridge/br_netfilter_ipv6.c:183 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0x127f/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x989/0x30b0 net/core/dev.c:6093 __netif_receive_skb_one_core net/core/dev.c:6204 [inline] __netif_receive_skb net/core/dev.c:6319 [inline] process_backlog+0x706/0x1860 net/core/dev.c:6670 __napi_poll+0xaa/0x330 net/core/dev.c:7729 napi_poll net/core/dev.c:7792 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7949 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:ptep_get include/linux/pgtable.h:495 [inline] RIP: 0010:do_zap_pte_range mm/memory.c:1813 [inline] RIP: 0010:zap_pte_range mm/memory.c:1934 [inline] RIP: 0010:zap_pmd_range mm/memory.c:2020 [inline] RIP: 0010:zap_pud_range mm/memory.c:2048 [inline] RIP: 0010:zap_p4d_range mm/memory.c:2069 [inline] RIP: 0010:__zap_vma_range+0xee9/0x4f10 mm/memory.c:2109 Code: 83 e6 10 31 ff e8 17 4b ad ff 48 83 e3 10 4c 89 74 24 40 0f 85 d3 2b 00 00 48 8b 5c 24 18 48 89 d8 48 c1 e8 03 42 80 3c 20 00 <74> 08 48 89 df e8 dd d7 1a 00 48 8b 03 48 89 44 24 30 4d 89 ef 49 RSP: 0018:ffffc900037773a0 EFLAGS: 00000246 RAX: 1ffff11004a1c880 RBX: ffff8880250e4400 RCX: ffff88802ae38000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003777690 R08: ffffea0001ab2133 R09: 1ffffd4000356426 R10: dffffc0000000000 R11: fffff94000356427 R12: dffffc0000000000 R13: 00007f091fe00000 R14: 00007f091fc80000 R15: ffff88802ae38000 unmap_vmas+0x390/0x550 mm/memory.c:2178 exit_mmap+0x293/0x9f0 mm/mmap.c:1300 __mmput+0x118/0x420 kernel/fork.c:1182 exit_mm+0x221/0x2d0 kernel/exit.c:610 do_exit+0x6cd/0x2360 kernel/exit.c:992 do_group_exit+0x22d/0x2f0 kernel/exit.c:1147 get_signal+0x121b/0x12c0 kernel/signal.c:3038 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f092099ce59 Code: Unable to access opcode bytes at 0x7f092099ce2f. RSP: 002b:00007f092177b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000031 RAX: 0000000000000000 RBX: 00007f0920c15fa0 RCX: 00007f092099ce59 RDX: 0000000000000010 RSI: 00002000000000c0 RDI: 0000000000000003 RBP: 00007f0920a32e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0920c16038 R14: 00007f0920c15fa0 R15: 00007ffcb93a2128 net_ratelimit: 12653 callbacks suppressed bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:66:a7:19:57:41:19, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:66:a7:19:57:41:19, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) net_ratelimit: 15807 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:66:a7:19:57:41:19, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:66:a7:19:57:41:19, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)