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) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6058/2:b..l rcu: (detected by 1, t=10502 jiffies, g=11905, q=2176 ncpus=2) task:syz.3.26 state:R running task stack:25320 pid:6058 tgid:6046 ppid:5847 task_flags:0x20400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6790 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7113 irqentry_exit+0x36/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5875 Code: d8 37 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 22 86 11 0f 0f 82 74 02 00 00 8b 35 ea b7 11 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 b9 d7 37 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc900047d6bf0 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e5c4d00 RCX: 00000000c639c71c RDX: 0000000000000000 RSI: ffffffff8de072fa RDI: ffffffff8c1578e0 RBP: 0000000000000002 R08: f501fefe41178ce3 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kmalloc_noprof include/linux/slab.h:905 [inline] slab_free_hook mm/slub.c:2333 [inline] slab_free mm/slub.c:4643 [inline] kmem_cache_free+0x142/0x4d0 mm/slub.c:4745 mempool_free+0xea/0x3b0 mm/mempool.c:548 bio_put_percpu_cache block/bio.c:801 [inline] bio_put+0x355/0x5b0 block/bio.c:820 bio_endio+0x70a/0x850 block/bio.c:1645 blk_update_request+0x96b/0x1630 block/blk-mq.c:987 blk_mq_end_request+0x5b/0x630 block/blk-mq.c:1149 blk_mq_complete_request block/blk-mq.c:1327 [inline] blk_mq_complete_request+0x8b/0xb0 block/blk-mq.c:1324 nullb_complete_cmd drivers/block/null_blk/main.c:1402 [inline] null_handle_cmd drivers/block/null_blk/main.c:1454 [inline] null_queue_rq+0xb69/0xfd0 drivers/block/null_blk/main.c:1693 null_queue_rqs+0xe9/0x2f0 drivers/block/null_blk/main.c:1707 __blk_mq_flush_list block/blk-mq.c:2826 [inline] __blk_mq_flush_list+0x97/0xc0 block/blk-mq.c:2822 blk_mq_dispatch_queue_requests+0x184/0x7b0 block/blk-mq.c:2871 blk_mq_flush_plug_list+0x1f2/0x600 block/blk-mq.c:2959 blk_add_rq_to_plug+0x1ca/0x540 block/blk-mq.c:1388 blk_mq_submit_bio+0x18d5/0x26a0 block/blk-mq.c:3208 __submit_bio+0x3cf/0x690 block/blk-core.c:635 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x660/0xd30 block/blk-core.c:751 submit_bio_noacct+0x50d/0x1eb0 block/blk-core.c:874 __block_write_full_folio+0x735/0xe00 fs/buffer.c:1939 block_write_full_folio+0x341/0x400 fs/buffer.c:2760 blkdev_writepages+0xb8/0x140 block/fops.c:483 do_writepages+0x277/0x600 mm/page-writeback.c:2636 filemap_fdatawrite_wbc mm/filemap.c:386 [inline] filemap_fdatawrite_wbc+0x104/0x160 mm/filemap.c:376 __filemap_fdatawrite_range+0xb2/0xf0 mm/filemap.c:419 filemap_write_and_wait_range mm/filemap.c:691 [inline] filemap_write_and_wait_range+0xa3/0x130 mm/filemap.c:682 filemap_write_and_wait include/linux/pagemap.h:68 [inline] sync_blockdev block/bdev.c:260 [inline] sync_blockdev block/bdev.c:256 [inline] bdev_release+0x4d3/0x6d0 block/bdev.c:1126 blkdev_release+0x15/0x20 block/fops.c:684 __fput+0x402/0xb70 fs/file_table.c:465 task_work_run+0x150/0x240 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x3f6/0x490 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc12758e929 RSP: 002b:00007fc128488038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fc1277b6160 RCX: 00007fc12758e929 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000002 RBP: 00007fc127610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc1277b6160 R15: 00007ffce40b6528 rcu: rcu_preempt kthread starved for 2135 jiffies! g11905 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:27672 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6790 __schedule_loop kernel/sched/core.c:6868 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6883 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 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: CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-rc5-syzkaller-00193-g40f92e79b0aa #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:console_flush_all+0x9a2/0xc60 kernel/printk/printk.c:3227 Code: 00 e8 c2 45 28 00 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 90 71 20 00 48 85 db 0f 85 55 01 00 00 e8 12 76 20 00 fb 4c 89 e0 <48> c1 e8 03 42 80 3c 38 00 0f 84 11 ff ff ff 4c 89 e7 e8 17 59 86 RSP: 0018:ffffc90000a08000 EFLAGS: 00000246 RAX: ffffffff8f2eda18 RBX: 0000000000000000 RCX: ffffffff819aed50 RDX: ffff88801e6bda00 RSI: ffffffff819aed5e RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff8f2eda18 R13: ffffffff8f2ed9c0 R14: ffffc90000a08090 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888124821000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f619a5cf000 CR3: 00000000125ae000 CR4: 00000000003526f0 Call Trace: __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xd8/0x210 kernel/printk/printk.c:3325 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450 _printk+0xc7/0x100 kernel/printk/printk.c:2475 br_fdb_update+0x4ad/0x7c0 net/bridge/br_fdb.c:897 br_handle_frame_finish+0xdc0/0x1ca0 net/bridge/br_input.c:144 br_nf_hook_thresh+0x307/0x410 net/bridge/br_netfilter_hooks.c:1170 br_nf_pre_routing_finish_ipv6+0x76a/0xfb0 net/bridge/br_netfilter_ipv6.c:154 NF_HOOK include/linux/netfilter.h:317 [inline] br_nf_pre_routing_ipv6+0x3cd/0x8c0 net/bridge/br_netfilter_ipv6.c:184 br_nf_pre_routing+0x860/0x15b0 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_bridge_pre net/bridge/br_input.c:283 [inline] br_handle_frame+0xad5/0x14b0 net/bridge/br_input.c:434 __netif_receive_skb_core.constprop.0+0xa26/0x4a00 net/core/dev.c:5863 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:5975 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6090 process_backlog+0x442/0x15e0 net/core/dev.c:6442 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7414 napi_poll net/core/dev.c:7478 [inline] net_rx_action+0xa9f/0xfe0 net/core/dev.c:7605 handle_softirqs+0x219/0x8e0 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 2b 6f 02 e9 93 fb 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 93 a7 25 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df8 EFLAGS: 000002c6 RAX: 0000000000786e83 RBX: 0000000000000001 RCX: ffffffff8b846c49 RDX: 0000000000000000 RSI: ffffffff8de2c763 RDI: ffffffff8c1578e0 RBP: ffffed1003cd7b40 R08: 0000000000000001 R09: ffffed10170a6645 R10: ffff8880b853322b R11: 0000000000000001 R12: 0000000000000001 R13: ffff88801e6bda00 R14: ffffffff90a99e50 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:749 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x148 net_ratelimit: 9100 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: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 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)