rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P25604/1:b..l rcu: (detected by 1, t=10503 jiffies, g=130685, q=2695 ncpus=2) task:cmp state:R running task stack:23528 pid:25604 tgid:25604 ppid:25589 task_flags:0x40000c flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7556 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8f0 kernel/entry/common.c:167 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:lock_acquire+0xaf/0x350 kernel/locking/lockdep.c:5844 Code: 3d 85 e9 b4 0e 00 0f 84 ce 00 00 00 65 8b 05 28 ce ca 11 85 c0 0f 85 bf 00 00 00 65 48 8b 05 30 89 ca 11 83 b8 9c 0b 00 00 00 <0f> 85 aa 00 00 00 4c 89 74 24 10 4d 89 fe 9c 41 5f fa 48 c7 c7 fe RSP: 0018:ffffc900065a73e8 EFLAGS: 00000246 RAX: ffff888032403e00 RBX: 0000000000000000 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff8177829c RDI: 1ffffffff1d6b38c RBP: ffffffff8177827f R08: 0000000000000000 R09: 0000000000000000 R10: ffffc900065a75d8 R11: fffff52000cb4ebd R12: 0000000000000002 R13: ffffffff8eb59c60 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:840 [inline] class_rcu_constructor include/linux/rcupdate.h:1183 [inline] unwind_next_frame+0xac/0x2550 arch/x86/kernel/unwind_orc.c:495 __unwind_start+0x514/0x660 arch/x86/kernel/unwind_orc.c:787 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 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x32d/0x660 mm/slub.c:5489 _kmalloc_noprof include/linux/slab.h:988 [inline] slab_free_hook mm/slub.c:2629 [inline] slab_free mm/slub.c:6377 [inline] kmem_cache_free+0x156/0x650 mm/slub.c:6504 tear_down_vmas+0x312/0x520 mm/mmap.c:1262 exit_mmap+0x4ca/0x9f0 mm/mmap.c:1320 __mmput+0x118/0x420 kernel/fork.c:1187 exit_mm+0x221/0x2d0 kernel/exit.c:615 do_exit+0x6cd/0x2360 kernel/exit.c:997 do_group_exit+0x22d/0x2f0 kernel/exit.c:1152 __do_sys_exit_group kernel/exit.c:1163 [inline] __se_sys_exit_group kernel/exit.c:1161 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1161 x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbd7fce76c5 RSP: 002b:00007fffac68f2c8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007fbd7fde8fe8 RCX: 00007fbd7fce76c5 RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000 RBP: 0000000000000001 R08: 00007fffac68f258 R09: 0000000000000000 R10: 00007fffac68f0f0 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbd7fde7680 R15: 00007fbd7fde9000 rcu: rcu_preempt kthread starved for 10418 jiffies! g130685 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:27400 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: CPU: 1 UID: 0 PID: 15145 Comm: kworker/R-bond9 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: bond9 bond_alb_monitor RIP: 0010:unwind_next_frame+0xd09/0x2550 arch/x86/kernel/unwind_orc.c:645 Code: 18 74 08 48 89 df e8 96 0f bd 00 48 8b 04 24 48 89 03 ba 10 00 00 00 49 8d 5e 50 48 89 df 31 f6 e8 5c 11 bd 00 48 8b 54 24 08 c7 04 00 00 48 89 5c 24 48 49 8d 7e 08 48 89 fb 48 c1 eb 03 42 RSP: 0000:ffffc90000a08540 EFLAGS: 00000246 RAX: ffffc90000a08638 RBX: ffffc90000a08638 RCX: 0000000000000000 RDX: ffffffff91834494 RSI: 0000000000000000 RDI: ffffc90000a08648 RBP: 1ffffffff2306892 R08: ffffc90000a08647 R09: 0000000000000000 R10: ffffc90000a08638 R11: fffff520001410c9 R12: dffffc0000000000 R13: ffffffff91834490 R14: ffffc90000a085e8 R15: ffffc90000a08630 FS: 0000000000000000(0000) GS:ffff88812504c000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555788cfdbe0 CR3: 000000000e946000 CR4: 00000000003526f0 Call Trace: 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+0x40/0x50 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:2677 [inline] slab_free mm/slub.c:6377 [inline] kmem_cache_free+0x182/0x650 mm/slub.c:6504 kfree_skb_reason include/linux/skbuff.h:1323 [inline] kfree_skb include/linux/skbuff.h:1332 [inline] ip6_mc_input+0x909/0xbc0 net/ipv6/ip6_input.c:638 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:325 __netif_receive_skb_one_core net/core/dev.c:6241 [inline] __netif_receive_skb net/core/dev.c:6354 [inline] process_backlog+0x774/0x1860 net/core/dev.c:6705 __napi_poll+0xaa/0x330 net/core/dev.c:7764 napi_poll net/core/dev.c:7827 [inline] net_rx_action+0x61d/0xf50 net/core/dev.c:7984 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:206 Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 4a 87 cc f5 48 89 df e8 a2 fc cc f5 e8 0d dd f8 f5 fb bf 01 00 00 00 52 10 be f5 65 8b 05 4b e0 96 07 85 c0 74 07 5b c3 cc cc cc cc RSP: 0000:ffffc900053dfad0 EFLAGS: 00000202 RAX: 0000000000039fd5 RBX: ffff88801b0cb000 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff8e23666e RDI: 0000000000000001 RBP: ffffc900053dfce0 R08: ffffffff90576d37 R09: 1ffffffff20aeda6 R10: dffffc0000000000 R11: fffffbfff20aeda7 R12: 0000000002000000 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88804d5e1378 process_one_work kernel/workqueue.c:3291 [inline] process_scheduled_works+0x90f/0x14e0 kernel/workqueue.c:3405 rescuer_thread+0x7b6/0x10b0 kernel/workqueue.c:3629 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ip6_tunnel: ip6tnl2 xmit: Local address not yet configured! ip6_tunnel: ip6gre1 xmit: Local address not yet configured! bridge0: received packet on veth1_to_bridge with own address as source address (addr:7e:04:86:d1:fd:fe, 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)