bridge0: received packet on bridge_slave_1 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): P2158/1:b..l rcu: (detected by 0, t=10503 jiffies, g=183257, q=10390 ncpus=2) task:syz.2.5053 state:R running task stack:23968 pid:2158 tgid:2157 ppid:450 task_flags:0x20400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7288 irqentry_exit+0x6f/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__rcu_read_unlock+0x63/0xe0 kernel/rcu/tree_plugin.h:443 Code: 75 1d 4c 8d b7 48 04 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 38 84 c0 75 66 41 83 3e 00 75 27 43 0f b6 04 3c 84 c0 75 41 8b 03 <3d> 00 00 00 40 73 0f 5b 41 5c 41 5d 41 5e 41 5f e9 48 c5 e0 09 cc RSP: 0018:ffffc9000aa8e468 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffff888033ada244 RCX: 576edc0c1c95d400 RDX: ffffc9000aa8e501 RSI: ffffffff8c04e5e0 RDI: ffff888033ad9e00 RBP: dffffc0000000000 R08: ffffc9000aa8fcf0 R09: 0000000000000000 R10: ffffc9000aa8e5b8 R11: fffff52001551cb9 R12: 1ffff1100675b448 R13: ffffc9000aa88000 R14: ffffc9000aa8e568 R15: dffffc0000000000 rcu_read_unlock include/linux/rcupdate.h:873 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x19ae/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:559 __call_rcu_common kernel/rcu/tree.c:3123 [inline] call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243 slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x309/0x400 mm/slub.c:4782 blk_update_request+0x57e/0xe60 block/blk-mq.c:989 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1151 >::end_ok rust/kernel/block/mq/request.rs:129 [inline] ::queue_rq drivers/block/rnull.rs:69 [inline] >::queue_rq_callback+0x1b6/0x2a0 rust/kernel/block/mq/operations.rs:94 blk_mq_dispatch_rq_list+0x4bd/0x1900 block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xda4/0x1570 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0xd7/0x190 block/blk-mq-sched.c:329 blk_mq_run_hw_queue+0x404/0x4f0 block/blk-mq.c:2358 blk_mq_dispatch_list+0xd0c/0xe00 include/linux/spinlock.h:-1 blk_mq_flush_plug_list+0x469/0x550 block/blk-mq.c:2967 __blk_flush_plug+0x3d3/0x4b0 block/blk-core.c:1220 blk_finish_plug+0x5e/0x90 block/blk-core.c:1247 blkdev_writepages+0x10e/0x170 block/fops.c:484 do_writepages+0x32e/0x550 mm/page-writeback.c:2634 filemap_fdatawrite_wbc mm/filemap.c:386 [inline] __filemap_fdatawrite_range mm/filemap.c:419 [inline] file_write_and_wait_range+0x23e/0x340 mm/filemap.c:794 blkdev_fsync+0x74/0xd0 block/fops.c:615 generic_write_sync+0x1b3/0x290 include/linux/fs.h:3036 blkdev_write_iter+0x5fa/0x710 block/fops.c:800 iter_file_splice_write+0x975/0x10e0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x101/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5a5/0xcc0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x181/0x270 fs/splice.c:1230 do_sendfile+0x4da/0x7e0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f998ad8ebe9 RSP: 002b:00007f998bcac038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f998afc5fa0 RCX: 00007f998ad8ebe9 RDX: 0000000000000000 RSI: 0000000000000007 RDI: 0000000000000007 RBP: 00007f998ae11e19 R08: 0000000000000000 R09: 0000000000000000 R10: 000000007ffff000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f998afc6038 R14: 00007f998afc5fa0 R15: 00007ffeaccc1628 rcu: rcu_preempt kthread starved for 253 jiffies! g183257 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:27344 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 2177 Comm: kworker/u8:6 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:stack_trace_consume_entry+0x130/0x280 kernel/stacktrace.c:95 Code: 49 89 e8 4c 89 e2 48 89 de 49 89 37 41 8b 18 41 0f b6 44 15 00 84 c0 0f 85 34 01 00 00 41 3b 1e 0f 92 c0 48 83 c4 18 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 44 89 c1 80 e1 07 80 c1 03 RSP: 0018:ffffc90000a07960 EFLAGS: 00000296 RAX: 0000000000000001 RBX: ffffc90000a07a40 RCX: ebcbd5cb547b1700 RDX: dffffc0000000000 RSI: ffffffff8971ba82 RDI: ffffc90000a07a40 RBP: 1ffff92000140f4a R08: ffffc90000a07a50 R09: 0000000000000011 R10: ffffc90000a079d8 R11: ffffffff81ad6180 R12: ffff88802aef9e00 R13: 1ffff92000140f49 R14: ffffc90000a07a48 R15: ffffc90000a07b58 FS: 0000000000000000(0000) GS:ffff8881258c4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005610d58aa168 CR3: 0000000032640000 CR4: 00000000003526f0 Call Trace: arch_stack_walk+0x10d/0x150 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4782 kfree_skb_reason include/linux/skbuff.h:1316 [inline] kfree_skb include/linux/skbuff.h:1325 [inline] ip6_mc_input+0x8f4/0xaf0 net/ipv6/ip6_input.c:593 ip_sabotage_in+0x1de/0x270 net/bridge/br_netfilter_hooks.c:993 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:273 [inline] NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:316 __netif_receive_skb_one_core net/core/dev.c:5991 [inline] __netif_receive_skb+0xd3/0x380 net/core/dev.c:6104 netif_receive_skb_internal net/core/dev.c:6190 [inline] netif_receive_skb+0x1cb/0x790 net/core/dev.c:6249 NF_HOOK+0xa0/0x390 include/linux/netfilter.h:319 br_handle_frame_finish+0x14d1/0x19b0 net/bridge/br_input.c:-1 br_nf_hook_thresh+0x3c3/0x4a0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x999/0xd60 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x37e/0x6b0 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline] nf_hook_bridge_pre net/bridge/br_input.c:283 [inline] br_handle_frame+0x982/0x14c0 net/bridge/br_input.c:434 __netif_receive_skb_core+0x10b9/0x4020 net/core/dev.c:5878 __netif_receive_skb_one_core net/core/dev.c:5989 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6104 process_backlog+0x60e/0x14f0 net/core/dev.c:6456 __napi_poll+0xc4/0x360 net/core/dev.c:7506 napi_poll net/core/dev.c:7569 [inline] net_rx_action+0x707/0xe30 net/core/dev.c:7696 handle_softirqs+0x283/0x870 kernel/softirq.c:579 do_softirq+0xec/0x180 kernel/softirq.c:480 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:835 [inline] nsim_dev_trap_report_work+0x7c7/0xb80 drivers/net/netdevsim/dev.c:866 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 net_ratelimit: 23819 callbacks suppressed bridge0: received packet on veth1_to_bridge with own address as source address (addr:42:a8:63:7e:8c:b0, 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: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: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:1c, vlan:0) bridge0: received packet on veth1_to_bridge with own address as source address (addr:36:bf:94:36:8e:8d, 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:0c, vlan:0)