syzbot

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): P8593/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=34449, q=3675 ncpus=2)
task:syz.1.628       state:R  running task     stack:23672 pid:8593  tgid:8593  ppid:5835   task_flags:0x400640 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7188
 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7512
 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:476 [inline]
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
 irqentry_exit+0x1fe/0x790 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5872
Code: 05 3b c2 2e 12 83 f8 07 0f 87 d9 02 00 00 48 0f a3 05 46 b8 f6 0e 0f 82 a4 02 00 00 8b 35 ce eb f6 0e 85 f6 0f 85 bf 00 00 00 <48> 8b 44 24 30 65 48 2b 05 dd c1 2e 12 0f 85 ed 02 00 00 48 83 c4
RSP: 0018:ffffc90004556310 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8df341ae RDI: ffffffff8c1c1f80
RBP: ffffffff8e7e5460 R08: 00000000b42e4f2c R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 rcu_read_lock include/linux/rcupdate.h:838 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
 unwind_next_frame+0xd1/0x2090 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 save_stack+0x162/0x1e0 mm/page_owner.c:165
 __set_page_owner+0x8c/0x540 mm/page_owner.c:341
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1858
 prep_new_page mm/page_alloc.c:1866 [inline]
 get_page_from_freelist+0x11a6/0x33b0 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5226
 alloc_pages_mpol+0x1fb/0x540 mm/mempolicy.c:2490
 folio_alloc_mpol_noprof+0x36/0x260 mm/mempolicy.c:2509
 shmem_alloc_folio+0x135/0x160 mm/shmem.c:1933
 shmem_alloc_and_add_folio+0x371/0xd40 mm/shmem.c:1975
 shmem_get_folio_gfp+0x6ab/0x1900 mm/shmem.c:2564
 shmem_get_folio mm/shmem.c:2670 [inline]
 shmem_write_begin+0x1a4/0x420 mm/shmem.c:3303
 generic_perform_write+0x292/0xa40 mm/filemap.c:4325
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3478
 __kernel_write_iter+0x2ac/0x920 fs/read_write.c:621
 dump_emit_page fs/coredump.c:1304 [inline]
 dump_user_range+0x3f9/0xad0 fs/coredump.c:1378
 elf_core_dump+0x2d5f/0x3d10 fs/binfmt_elf.c:2109
 coredump_write fs/coredump.c:1053 [inline]
 do_coredump fs/coredump.c:1132 [inline]
 vfs_coredump+0x29a0/0x5770 fs/coredump.c:1206
 get_signal+0x1f2a/0x21e0 kernel/signal.c:3022
 arch_do_signal_or_restart+0x91/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:98 [inline]
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:252 [inline]
 irqentry_exit_to_user_mode include/linux/irq-entry-common.h:323 [inline]
 irqentry_exit+0x403/0x790 kernel/entry/common.c:162
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f4332d9c821
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f4333016090 RCX: 00007f4332d9c819
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007f4332e32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f4333016128 R14: 00007f4333016090 R15: 00007ffddbecacc8
 </TASK>
rcu: rcu_preempt kthread starved for 669 jiffies! g34449 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:28904 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7282
 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
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: 498 Comm: kworker/u8:6 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x2f/0x70 kernel/kcov.c:217
Code: 8b 05 45 a5 0a 12 48 8b 34 24 65 48 8b 15 21 a5 0a 12 a9 00 01 ff 00 74 1b f6 c4 01 74 07 a9 00 00 ff 00 74 05 e9 d1 ef 93 09 <8b> 82 cc 16 00 00 85 c0 74 f1 8b 82 a8 16 00 00 83 f8 02 75 e6 48
RSP: 0018:ffffc90000a07e88 EFLAGS: 00000246
RAX: 0000000000000101 RBX: 0000000000000002 RCX: ffffffff89b25c15
RDX: ffff88802630ca00 RSI: ffffffff8a591ad8 RDI: ffff888037f51000
RBP: ffff88801eba4000 R08: 0000000000000004 R09: 0000000000000004
R10: 0000000000000002 R11: 0000000000000000 R12: 1ffff92000140ff3
R13: ffff88816f14d640 R14: ffff88807b0e6b28 R15: ffffc90000a08110
FS:  0000000000000000(0000) GS:ffff8881243de000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000003fd030 CR3: 000000000e596000 CR4: 00000000003526f0
DR0: 0000000000000008 DR1: 0000000000000002 DR2: 0000000000000081
DR3: ffffffffefffff14 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 ip6t_do_table+0x128/0x1c90 net/ipv6/netfilter/ip6_tables.c:266
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xbf/0x220 net/netfilter/core.c:619
 nf_hook+0x2f3/0x7a0 include/linux/netfilter.h:273
 NF_HOOK include/linux/netfilter.h:316 [inline]
 br_nf_forward_ip.part.0+0x5f3/0x820 net/bridge/br_netfilter_hooks.c:717
 br_nf_forward_ip net/bridge/br_netfilter_hooks.c:677 [inline]
 br_nf_forward+0xfe5/0x19f0 net/bridge/br_netfilter_hooks.c:774
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_slow+0xbf/0x220 net/netfilter/core.c:619
 nf_hook include/linux/netfilter.h:273 [inline]
 NF_HOOK include/linux/netfilter.h:316 [inline]
 __br_forward+0x2f7/0x970 net/bridge/br_forward.c:115
 deliver_clone net/bridge/br_forward.c:131 [inline]
 br_flood+0x37f/0x650 net/bridge/br_forward.c:250
 br_handle_frame_finish+0xff4/0x1f60 net/bridge/br_input.c:229
 br_nf_hook_thresh+0x30d/0x420 net/bridge/br_netfilter_hooks.c:1161
 br_nf_pre_routing_finish_ipv6+0x659/0xdd0 net/bridge/br_netfilter_ipv6.c:153
 NF_HOOK include/linux/netfilter.h:318 [inline]
 br_nf_pre_routing_ipv6+0x39c/0x8b0 net/bridge/br_netfilter_ipv6.c:183
 br_nf_pre_routing+0x90f/0x1560 net/bridge/br_netfilter_hooks.c:509
 nf_hook_entry_hookfn include/linux/netfilter.h:158 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:291 [inline]
 br_handle_frame+0xcdd/0x1520 net/bridge/br_input.c:442
 __netif_receive_skb_core.constprop.0+0x6c5/0x3530 net/core/dev.c:6096
 __netif_receive_skb_one_core+0xb0/0x1e0 net/core/dev.c:6207
 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6322
 process_backlog+0x37a/0x1580 net/core/dev.c:6673
 __napi_poll.constprop.0+0xaf/0x450 net/core/dev.c:7737
 napi_poll net/core/dev.c:7800 [inline]
 net_rx_action+0xa40/0xf20 net/core/dev.c:7957
 handle_softirqs+0x1ea/0xa00 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1061
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x58e/0x1700 kernel/smp.c:892
Code: 00 fc ff df 48 8b 54 24 08 49 89 d5 49 89 d4 49 c1 ed 03 41 83 e4 07 49 01 c5 41 83 c4 03 e8 09 80 0c 00 f3 90 41 0f b6 45 00 <41> 38 c4 7c 08 84 c0 0f 85 63 0f 00 00 8b 45 08 31 ff 83 e0 01 41
RSP: 0018:ffffc900037c7870 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81fcfafd
RDX: ffff88802630ca00 RSI: ffffffff81fcfad7 RDI: ffff88802630ca00
RBP: ffff8880b8443320 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000003
R13: ffffed1017088665 R14: 0000000000000001 R15: ffff8880b853c5c0
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1057
 on_each_cpu include/linux/smp.h:72 [inline]
 smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
 smp_text_poke_batch_finish+0x337/0xc60 arch/x86/kernel/alternative.c:2983
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 jump_label_update+0x37a/0x550 kernel/jump_label.c:910
 static_key_enable_cpuslocked+0x1bc/0x270 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate mm/kfence/core.c:906 [inline]
 toggle_allocation_gate+0xfe/0x2d0 mm/kfence/core.c:898
 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
 process_scheduled_works kernel/workqueue.c:3385 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
net_ratelimit: 15941 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 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: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:16:64:59:a5:7d:f6, 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 bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)
net_ratelimit: 26622 callbacks suppressed
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:1c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:16:64:59:a5:7d:f6, 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 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)