bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0) rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6730/2:b..l rcu: (detected by 1, t=10503 jiffies, g=18233, q=1912 ncpus=2) task:syz.1.150 state:R running task stack:25000 pid:6730 tgid:6729 ppid:5836 task_flags:0x20400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7090 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:218 [inline] RIP: 0010:unwind_next_frame+0x23d/0x20a0 arch/x86/kernel/unwind_orc.c:494 Code: 89 74 24 20 89 44 24 18 e8 f0 99 b5 00 48 8b 4c 24 30 48 8b 44 24 28 8b 74 24 20 44 8b 5c 24 18 8d 50 01 8b 0c 8d fc a7 d3 91 <48> b8 00 00 00 00 00 fc ff df 48 8d 3c 95 fc a7 d3 91 49 89 f8 49 RSP: 0018:ffffc9000c066948 EFLAGS: 00000246 RAX: 000000000003ab51 RBX: 0000000000000001 RCX: 00000000000ab630 RDX: 000000000003ab52 RSI: 00000000000a6d52 RDI: ffffffff91e25540 RBP: ffffc9000c066a00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 000000000003ab51 R12: ffffc9000c066a08 R13: ffffc9000c0669b8 R14: ffffc9000c0669ed R15: ffffffff84ab51bc 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_record_aux_stack+0xb8/0xd0 mm/kasan/generic.c:548 slab_free_hook mm/slub.c:2341 [inline] slab_free mm/slub.c:4642 [inline] kmem_cache_free+0x160/0x4d0 mm/slub.c:4744 mempool_free+0xe7/0x3b0 mm/mempool.c:548 bio_put_percpu_cache block/bio.c:800 [inline] bio_put+0x355/0x5b0 block/bio.c:819 bio_endio+0x6d2/0x810 block/bio.c:1551 blk_update_request+0x96b/0x1630 block/blk-mq.c:983 blk_mq_end_request+0x5b/0x620 block/blk-mq.c:1145 blk_mq_complete_request block/blk-mq.c:1323 [inline] blk_mq_complete_request+0x8b/0xb0 block/blk-mq.c:1320 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_plug_list block/blk-mq.c:2825 [inline] __blk_mq_flush_plug_list+0x9a/0xc0 block/blk-mq.c:2820 blk_mq_flush_plug_list+0x1698/0x1c70 block/blk-mq.c:2904 blk_add_rq_to_plug+0x1ca/0x540 block/blk-mq.c:1384 blk_mq_submit_bio+0x19b4/0x2600 block/blk-mq.c:3156 __submit_bio+0x3cf/0x690 block/blk-core.c:635 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x663/0xd30 block/blk-core.c:751 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:874 __block_write_full_folio+0x735/0xe00 fs/buffer.c:1937 block_write_full_folio+0x341/0x400 fs/buffer.c:2758 write_cache_pages+0xaf/0x130 mm/page-writeback.c:2613 blkdev_writepages+0xa5/0xf0 block/fops.c:458 do_writepages+0x1b2/0x820 mm/page-writeback.c:2656 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:660 __fput+0x3ff/0xb70 fs/file_table.c:465 task_work_run+0x14d/0x240 kernel/task_work.c:227 get_signal+0x1d1/0x26d0 kernel/signal.c:2807 arch_do_signal_or_restart+0x8f/0x7a0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f169798e969 RSP: 002b:00007f1698729038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: 0000000000400000 RBX: 00007f1697bb5fa0 RCX: 00007f169798e969 RDX: 000000007fffffff RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f1697a10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1697bb5fa0 R15: 00007ffd50ec5e68 rcu: rcu_preempt kthread starved for 289 jiffies! g18233 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:27704 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:153 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 6.15.0-rc6-syzkaller-00208-g3c21441eeffc #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:write_comp_data+0x11/0x90 kernel/kcov.c:246 Code: b1 09 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 49 89 d2 49 89 f8 49 89 f1 65 48 8b 15 67 c6 e8 11 <65> 8b 05 78 c6 e8 11 a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 RSP: 0018:ffffc90000a07c58 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000046 RCX: ffffffff89447951 RDX: ffff88801dadda00 RSI: 00000000000005ee RDI: 0000000000000004 RBP: ffff888039384dc0 R08: 0000000000000004 R09: 00000000000005ee R10: 0000000000000046 R11: 0000000000005bc7 R12: 00000000000005ee R13: 0000000000000001 R14: 0000000000000000 R15: ffff888039384e74 FS: 0000000000000000(0000) GS:ffff888124ae9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f649483ff18 CR3: 00000000697f2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __is_skb_forwardable include/linux/netdevice.h:4249 [inline] is_skb_forwardable+0x101/0x210 net/core/dev.c:2360 br_dev_queue_push_xmit+0x9e/0x8a0 net/bridge/br_forward.c:36 br_nf_dev_queue_xmit+0x6f3/0x2cb0 net/bridge/br_netfilter_hooks.c:923 NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] br_nf_post_routing+0x8e7/0x1190 net/bridge/br_netfilter_hooks.c:969 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xbb/0x200 net/netfilter/core.c:626 nf_hook+0x45e/0x780 include/linux/netfilter.h:269 NF_HOOK include/linux/netfilter.h:312 [inline] br_forward_finish+0xcd/0x130 net/bridge/br_forward.c:66 br_nf_hook_thresh+0x301/0x410 net/bridge/br_netfilter_hooks.c:1170 br_nf_forward_finish+0x66a/0xba0 net/bridge/br_netfilter_hooks.c:665 NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] br_nf_forward_ip.part.0+0x609/0x810 net/bridge/br_netfilter_hooks.c:719 br_nf_forward_ip net/bridge/br_netfilter_hooks.c:679 [inline] br_nf_forward+0xf0f/0x1be0 net/bridge/br_netfilter_hooks.c:776 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xbb/0x200 net/netfilter/core.c:626 nf_hook+0x45e/0x780 include/linux/netfilter.h:269 NF_HOOK include/linux/netfilter.h:312 [inline] __br_forward+0x1be/0x5b0 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] br_flood+0x39c/0x650 net/bridge/br_forward.c:249 br_handle_frame_finish+0xe8e/0x1c20 net/bridge/br_input.c:220 br_nf_hook_thresh+0x301/0x410 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:314 [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:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:282 [inline] br_handle_frame+0xad5/0x14a0 net/bridge/br_input.c:433 __netif_receive_skb_core.constprop.0+0xa23/0x4a00 net/core/dev.c:5773 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:5885 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6000 process_backlog+0x442/0x15e0 net/core/dev.c:6352 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7324 napi_poll net/core/dev.c:7388 [inline] net_rx_action+0xa97/0x1010 net/core/dev.c:7510 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:1049 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1049 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:81 Code: 06 65 02 e9 83 fc 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 c3 6e 20 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: 000002c2 RAX: 0000000000202915 RBX: 0000000000000001 RCX: ffffffff8b6983e9 RDX: 0000000000000000 RSI: ffffffff8dbdcd2f RDI: ffffffff8bf47460 RBP: ffffed1003b5bb40 R08: 0000000000000001 R09: ffffed10170a65bd R10: ffff8880b8532deb R11: 0000000000000000 R12: 0000000000000001 R13: ffff88801dadda00 R14: ffffffff90851f10 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:748 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 bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0) net_ratelimit: 13546 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:2e:25:4a:f4:48:8b, vlan:0)