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:36:d8:20:91:b4:a3, vlan:0) 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): P12130/1:b..l rcu: (detected by 1, t=10517 jiffies, g=52549, q=1296 ncpus=2) task:syz.0.1500 state:R running task stack:25608 pid:12130 tgid:12130 ppid:5613 task_flags:0x40044c flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7284 preempt_schedule_common+0x7f/0xd0 kernel/sched/core.c:7463 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:201 [inline] _raw_spin_unlock+0x41/0x50 kernel/locking/spinlock.c:213 spin_unlock include/linux/spinlock.h:401 [inline] zap_pte_range mm/memory.c:2095 [inline] zap_pmd_range mm/memory.c:2151 [inline] zap_pud_range mm/memory.c:2179 [inline] zap_p4d_range mm/memory.c:2200 [inline] __zap_vma_range+0x40e1/0x4f80 mm/memory.c:2240 unmap_vmas+0x390/0x550 mm/memory.c:2309 exit_mmap+0x293/0x9f0 mm/mmap.c:1315 __mmput+0x118/0x420 kernel/fork.c:1193 exit_mm+0x221/0x2d0 kernel/exit.c:618 do_exit+0x6cd/0x2360 kernel/exit.c:1000 do_group_exit+0x22d/0x2f0 kernel/exit.c:1155 get_signal+0x121b/0x12c0 kernel/signal.c:3112 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+0x10e/0x770 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:343 [inline] do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4342b9e159 RSP: 002b:00007ffc0374c538 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007ffc0374c620 RCX: 00007f4342b9e159 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 000000000004ea81 R08: 0000000000000001 R09: 0000000000000000 R10: 0000001b32820000 R11: 0000000000000246 R12: 00007ffc0374c660 R13: 00007f4342e25fac R14: 000000000004eacf R15: 00007f4342e25fa0 rcu: rcu_preempt kthread starved for 261 jiffies! g52549 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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:27496 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5533 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7284 __schedule_loop kernel/sched/core.c:7361 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7376 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330 kthread+0x38b/0x480 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: 79 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: krds_cp_wq#7/0 rds_send_worker RIP: 0010:check_wait_context kernel/locking/lockdep.c:4914 [inline] RIP: 0010:__lock_acquire+0x529/0x2de0 kernel/locking/lockdep.c:5238 Code: 45 89 e7 41 81 e7 ff ff ff 7f 83 f9 31 73 1d 4b 8d 0c bf 41 8b 8c ce d0 0b 00 00 31 c1 ff cb 49 ff cc f7 c1 00 60 00 00 74 cf 18 48 c7 c7 30 ac c2 8e 4c 89 fe e8 16 8c 79 03 48 8b 45 20 eb RSP: 0018:ffffc90000006ab8 EFLAGS: 00000006 RAX: 2500000000022007 RBX: 0000000000000002 RCX: 00000000000629d0 RDX: 0000000000000003 RSI: 0000000000022000 RDI: 2500000000000000 RBP: ffff88801db24ad0 R08: ffffffff8177f1df R09: 0000000000000000 R10: ffffc90000006d98 R11: ffffffff81b293f0 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88801db23e80 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff888124cca000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7cb79ed158 CR3: 00000000120f0000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 rcu_lock_acquire include/linux/rcupdate.h:309 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] class_rcu_constructor include/linux/rcupdate.h:1216 [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 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4683 [inline] slab_alloc_node mm/slub.c:4996 [inline] kmem_cache_alloc_noprof+0x2b9/0x600 mm/slub.c:5010 skb_ext_maybe_cow net/core/skbuff.c:7170 [inline] skb_ext_add+0x1b6/0x8e0 net/core/skbuff.c:7245 nf_bridge_unshare net/bridge/br_netfilter_hooks.c:170 [inline] br_nf_forward_ip+0xc3/0xa30 net/bridge/br_netfilter_hooks.c:686 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619 nf_hook include/linux/netfilter.h:280 [inline] NF_HOOK+0x23e/0x3f0 include/linux/netfilter.h:323 __br_forward+0x397/0x540 net/bridge/br_forward.c:115 br_handle_frame_finish+0x1119/0x1950 net/bridge/br_input.c:229 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:325 [inline] br_nf_pre_routing_ipv6+0x382/0x6f0 net/bridge/br_netfilter_ipv6.c:183 nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline] nf_hook_bridge_pre net/bridge/br_input.c:291 [inline] br_handle_frame+0x1329/0x1600 net/bridge/br_input.c:451 __netif_receive_skb_core+0x989/0x30c0 net/core/dev.c:6152 __netif_receive_skb_one_core net/core/dev.c:6263 [inline] __netif_receive_skb net/core/dev.c:6378 [inline] process_backlog+0x727/0x18b0 net/core/dev.c:6729 __napi_poll+0xaa/0x330 net/core/dev.c:7798 napi_poll net/core/dev.c:7861 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:8018 handle_softirqs+0x226/0x860 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] invoke_softirq kernel/softirq.c:519 [inline] __irq_exit_rcu+0xcb/0x220 kernel/softirq.c:758 irq_exit_rcu+0x9/0x30 kernel/softirq.c:775 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:finish_task_switch+0x413/0xc60 kernel/sched/core.c:5384 Code: 04 00 00 41 c7 84 24 20 0e 00 00 00 00 00 00 0f 1f 44 00 00 49 83 c4 48 4c 89 e7 e8 17 0e 53 0a e8 92 1a 3a 00 fb 4c 8b 65 c8 <49> 8d bc 24 10 17 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 RSP: 0018:ffffc9000201f580 EFLAGS: 00000202 RAX: 00000000001620f7 RBX: ffff8880b863c8e0 RCX: 8000000000000001 RDX: 0000000000000006 RSI: ffffffff8e41595b RDI: ffffffff8c6dac80 RBP: ffffc9000201f5d0 R08: ffffffff907a5f7f R09: 1ffffffff20f4bef R10: dffffc0000000000 R11: fffffbfff20f4bf0 R12: ffff88801db23e80 R13: ffff8880b863c8a8 R14: dffffc0000000000 R15: 1ffff110170c791c context_switch kernel/sched/core.c:5536 [inline] __schedule+0x17e3/0x58f0 kernel/sched/core.c:7284 preempt_schedule_common+0x7f/0xd0 kernel/sched/core.c:7463 preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0xe9/0x140 kernel/softirq.c:480 rds_send_xmit+0x4dc/0x2930 net/rds/send.c:260 rds_send_worker+0x7d/0x2e0 net/rds/threads.c:200 process_one_work kernel/workqueue.c:3396 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560 kthread+0x38b/0x480 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