bridge0: received packet on bridge_slave_0 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): P20536/1:b..l P2/1:b..l P20484/1:b..l P20537/1:b..l rcu: (detected by 0, t=10502 jiffies, g=248037, q=2725 ncpus=2) task:kworker/1:5 state:R running task stack:27912 pid:20537 tgid:20537 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: events legacy_dvb_usb_read_remote_control Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234 irqentry_exit+0x599/0x620 kernel/entry/common.c:239 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x20b/0x2e0 kernel/locking/lockdep.c:5872 Code: e9 30 ff ff ff e8 a5 5e 0a 0a f7 c3 00 02 00 00 0f 84 38 ff ff ff 65 48 8b 05 21 9c 79 11 48 3b 44 24 30 75 33 fb 48 83 c4 38 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 06 45 0d 0a cc 48 8d 3d 1e 2c 73 RSP: 0018:ffffc90005437338 EFLAGS: 00000282 RAX: 67048f7807ee7000 RBX: 0000000000000246 RCX: 0000000000000046 RDX: 0000000081349c3d RSI: ffffffff8e15c4cf RDI: ffffffff8c279800 RBP: 0000000000000000 R08: ffffffff81767a45 R09: ffffffff8e7603e0 R10: ffffc900054374f8 R11: fffff52000a86ea1 R12: 0000000000000002 R13: ffffffff8e7603e0 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 __unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:773 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1432 [inline] __free_frozen_pages+0xc00/0xd90 mm/page_alloc.c:2977 __slab_free+0x263/0x2b0 mm/slub.c:5490 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:406 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5297 kmalloc_noprof include/linux/slab.h:962 [inline] usb_control_msg+0x73/0x3e0 drivers/usb/core/message.c:144 m920x_read drivers/media/usb/dvb-usb/m920x.c:36 [inline] m920x_rc_query+0xcd/0x830 drivers/media/usb/dvb-usb/m920x.c:188 legacy_dvb_usb_read_remote_control+0x107/0x450 drivers/media/usb/dvb-usb/dvb-usb-remote.c:123 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 task:syz.5.6182 state:R running task stack:25232 pid:20484 tgid:20482 ppid:12731 task_flags:0x40044c flags:0x00080000 Call Trace: task:kthreadd state:R running task stack:26664 pid:2 tgid:2 ppid:0 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234 irqentry_exit+0x599/0x620 kernel/entry/common.c:239 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:unwind_next_frame+0x183/0x23c0 arch/x86/kernel/unwind_orc.c:-1 Code: e5 18 00 00 49 8d 5e 35 48 89 d8 48 c1 e8 03 48 89 44 24 28 0f b6 04 28 84 c0 0f 85 45 1b 00 00 4c 89 6c 24 48 4c 89 64 24 20 <4c> 89 7c 24 50 48 89 5c 24 18 0f b6 1b 48 8b 44 24 30 80 3c 28 00 RSP: 0018:ffffc90000076ff8 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc900000770fd RCX: 0000000080000001 RDX: 00000000a1697acb RSI: ffffffff8c2797e0 RDI: ffffffff8c2797a0 RBP: dffffc0000000000 R08: ffffffff81767a45 R09: ffffffff8e7603e0 R10: ffffc90000077118 R11: ffffffff81b0a7f0 R12: 1ffff9200000ee19 R13: ffffc90000077118 R14: ffffc900000770c8 R15: ffffffff81767a45 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1432 [inline] __free_frozen_pages+0xc00/0xd90 mm/page_alloc.c:2977 __slab_free+0x263/0x2b0 mm/slub.c:5490 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:406 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5177 [inline] __kmalloc_noprof+0x35c/0x760 mm/slub.c:5189 kmalloc_noprof include/linux/slab.h:966 [inline] kzalloc_noprof include/linux/slab.h:1204 [inline] __alloc_empty_sheaf mm/slub.c:2749 [inline] alloc_empty_sheaf mm/slub.c:2764 [inline] alloc_full_sheaf mm/slub.c:2803 [inline] __pcs_replace_empty_main+0x3cc/0x620 mm/slub.c:4546 alloc_from_pcs mm/slub.c:4639 [inline] slab_alloc_node mm/slub.c:4773 [inline] __kmalloc_cache_node_noprof+0x465/0x6b0 mm/slub.c:5305 kmalloc_node_noprof include/linux/slab.h:1093 [inline] __get_vm_area_node+0x13f/0x300 mm/vmalloc.c:3221 __vmalloc_node_range_noprof+0x372/0x1730 mm/vmalloc.c:4024 __vmalloc_node_noprof+0xc2/0x100 mm/vmalloc.c:4124 alloc_thread_stack_node kernel/fork.c:355 [inline] dup_task_struct+0x228/0x9a0 kernel/fork.c:924 copy_process+0x508/0x3cf0 kernel/fork.c:2050 kernel_clone+0x248/0x8e0 kernel/fork.c:2654 kernel_thread+0x13f/0x1b0 kernel/fork.c:2715 create_kthread kernel/kthread.c:490 [inline] kthreadd+0x4ec/0x6e0 kernel/kthread.c:849 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 task:udevd state:R running task stack:26624 pid:20536 tgid:20536 ppid:13887 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234 irqentry_exit+0x599/0x620 kernel/entry/common.c:239 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:60 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:409 [inline] RIP: 0010:deref_stack_reg+0xc3/0x230 arch/x86/kernel/unwind_orc.c:419 Code: 85 3c 01 00 00 41 83 3f 00 0f 95 c0 4c 39 c3 0f 96 c1 20 c1 4d 39 c6 0f 97 c0 20 c8 3c 01 75 18 49 8d 40 08 48 39 d8 0f 97 c1 <4c> 39 f0 0f 96 c0 84 c1 0f 85 c3 00 00 00 49 8d 7f 28 48 89 f8 48 RSP: 0018:ffffc90005486fe0 EFLAGS: 00000202 RAX: ffffc90005487520 RBX: ffffc90005480000 RCX: 0000000000000001 RDX: ffffc90005487148 RSI: dffffc0000000000 RDI: ffffc90005487108 RBP: 1ffff92000a90e21 R08: ffffc90005487518 R09: 0000000000000000 R10: ffffc90005487158 R11: fffff52000a90e2d R12: 1ffff92000a90e22 R13: 1ffff92000a90e23 R14: ffffc90005488000 R15: ffffc90005487108 unwind_next_frame+0x18c6/0x23c0 arch/x86/kernel/unwind_orc.c:-1 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 slab_free_hook mm/slub.c:2631 [inline] slab_free mm/slub.c:6082 [inline] kmem_cache_free+0x426/0x630 mm/slub.c:6212 anon_vma_free mm/rmap.c:137 [inline] __put_anon_vma+0x12b/0x2d0 mm/rmap.c:2863 put_anon_vma mm/internal.h:212 [inline] unlink_anon_vmas+0x58b/0x730 mm/rmap.c:529 free_pgtables+0x6f4/0x9a0 mm/memory.c:414 exit_mmap+0x44b/0xdb0 mm/mmap.c:1288 __mmput+0x118/0x430 kernel/fork.c:1174 exec_mmap+0x3b4/0x440 fs/exec.c:893 begin_new_exec+0x134a/0x24a0 fs/exec.c:1148 load_elf_binary+0xa47/0x2980 fs/binfmt_elf.c:1010 search_binary_handler fs/exec.c:1664 [inline] exec_binprm fs/exec.c:1696 [inline] bprm_execve+0x93d/0x1460 fs/exec.c:1748 do_execveat_common+0x50d/0x690 fs/exec.c:1846 __do_sys_execve fs/exec.c:1930 [inline] __se_sys_execve fs/exec.c:1924 [inline] __x64_sys_execve+0x97/0xc0 fs/exec.c:1924 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb1d84f2107 RSP: 002b:00007fffe39c3c38 EFLAGS: 00000202 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 0000558720bd4140 RCX: 00007fb1d84f2107 RDX: 00005587269fc690 RSI: 00007fffe39c3d50 RDI: 00007fffe39c4550 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000202 R12: 00005587269fc690 R13: 00007fffe39c3d50 R14: 000000000000000b R15: 0000000000000008 rcu: rcu_preempt kthread starved for 6163 jiffies! g248037 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:I stack:28104 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 42 Comm: kworker/1:1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:check_preemption_disabled+0x21/0xe0 lib/smp_processor_id.c:53 Code: 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 65 8b 05 57 23 6f 07 65 8b 0d 4c 23 6f 07 f7 c1 ff ff ff 7f 74 0c 5b 41 5e 41 5f <5d> c3 cc cc cc cc cc 9c 59 f7 c1 00 02 00 00 74 ea 65 4c 8b 3d fe RSP: 0018:ffffc90000a07960 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000202 RCX: 0000000080000101 RDX: 0000000000000005 RSI: ffffffff8e15c4cf RDI: ffffffff8c279800 RBP: ffff8880216bc860 R08: ffffc90000a08290 R09: 0000000000000000 R10: ffffc90000a07af8 R11: fffff52000140f61 R12: 0000000000000005 R13: 0000000000000005 R14: ffffffff8e7603e0 R15: ffff8880216bbc80 FS: 0000000000000000(0000) GS:ffff88812556f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdf29fb1019 CR3: 0000000035c0a000 CR4: 00000000003526f0 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline] lock_release+0x259/0x3d0 kernel/locking/lockdep.c:5891 rcu_lock_release include/linux/rcupdate.h:322 [inline] rcu_read_unlock include/linux/rcupdate.h:881 [inline] class_rcu_destructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0x1aaa/0x23c0 arch/x86/kernel/unwind_orc.c:695 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 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2670 [inline] slab_free mm/slub.c:6082 [inline] kmem_cache_free+0x187/0x630 mm/slub.c:6212 skb_ext_reset include/linux/skbuff.h:5090 [inline] skb_release_head_state+0x270/0x360 net/core/skbuff.c:1195 skb_release_all net/core/skbuff.c:1201 [inline] __kfree_skb+0x24/0x210 net/core/skbuff.c:1217 kfree_skb_reason include/linux/skbuff.h:1322 [inline] kfree_skb include/linux/skbuff.h:1331 [inline] ip6_mc_input+0x8de/0xbd0 net/ipv6/ip6_input.c:593 ip_sabotage_in+0x1e1/0x270 net/bridge/br_netfilter_hooks.c:990 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+0x21f/0x3c0 include/linux/netfilter.h:316 __netif_receive_skb_one_core net/core/dev.c:6149 [inline] __netif_receive_skb net/core/dev.c:6262 [inline] netif_receive_skb_internal net/core/dev.c:6348 [inline] netif_receive_skb+0x278/0xc50 net/core/dev.c:6407 NF_HOOK+0xa4/0x3a0 include/linux/netfilter.h:319 br_handle_frame_finish+0x14b2/0x1b40 net/bridge/br_input.c:-1 br_nf_hook_thresh+0x3dd/0x4c0 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0xa3a/0xd70 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:318 [inline] br_nf_pre_routing_ipv6+0x374/0x6f0 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:291 [inline] br_handle_frame+0x1277/0x1510 net/bridge/br_input.c:442 __netif_receive_skb_core+0x98f/0x31a0 net/core/dev.c:6036 __netif_receive_skb_one_core net/core/dev.c:6147 [inline] __netif_receive_skb net/core/dev.c:6262 [inline] process_backlog+0x76d/0x1950 net/core/dev.c:6614 __napi_poll+0xae/0x340 net/core/dev.c:7678 napi_poll net/core/dev.c:7741 [inline] net_rx_action+0x627/0xf70 net/core/dev.c:7893 handle_softirqs+0x22a/0x870 kernel/softirq.c:622 do_softirq+0x76/0xd0 kernel/softirq.c:523 __local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450 spin_unlock_bh include/linux/spinlock.h:395 [inline] neigh_periodic_work+0xc28/0xe50 net/core/neighbour.c:1038 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 net_ratelimit: 17623 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:be:e7:82:3c:6b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:be:e7:82:3c:6b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:0a:be:e7:82:3c:6b, 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:0a:be:e7:82:3c:6b, 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:0a:be:e7:82:3c:6b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)