rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10502 jiffies, g=135105, q=1648 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 1866 (4295057156-4295055290), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 1866 jiffies! g135105 f0x2 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:27032 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2046 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2248 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:__in6_dev_get include/net/addrconf.h:347 [inline] RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:443 [inline] RIP: 0010:find_match+0xb5/0xc90 net/ipv6/route.c:781 Code: df e8 ff 77 13 f8 48 89 d8 bb c0 00 00 00 48 03 18 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 de 77 13 f8 48 8b 1b 56 13 47 01 41 89 c4 31 ff 89 c6 e8 ba 86 b1 f7 45 85 e4 74 1a RSP: 0018:ffffc90000a07620 EFLAGS: 00000246 RAX: 1ffff110022d1818 RBX: ffff88805fffb000 RCX: 0000000000000100 RDX: ffff88801c6cda00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 1ffff1100fa0fa97 R08: ffffc90000a07920 R09: ffffc90000a07930 R10: ffffc90000a07780 R11: fffff52000140ef2 R12: dffffc0000000000 R13: 0000000000000003 R14: 1ffff1100fa0fa99 R15: ffff88807d07d4cf FS: 0000000000000000(0000) GS:ffff8881261cf000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f42197ffe38 CR3: 000000007e310000 CR4: 00000000003526f0 DR0: 0000000100000000 DR1: 0000000000000040 DR2: 0000000000000003 DR3: 0000000000000009 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __find_rr_leaf+0x23a/0x6d0 net/ipv6/route.c:869 find_rr_leaf net/ipv6/route.c:890 [inline] rt6_select net/ipv6/route.c:934 [inline] fib6_table_lookup+0x39f/0xa80 net/ipv6/route.c:2230 ip6_pol_route+0x222/0x1180 net/ipv6/route.c:2266 pol_lookup_func include/net/ip6_fib.h:616 [inline] fib6_rule_lookup+0x52f/0x6f0 net/ipv6/fib6_rules.c:120 ip6_route_input_lookup net/ipv6/route.c:2335 [inline] ip6_route_input+0x6ce/0xa50 net/ipv6/route.c:2631 ip6_rcv_finish+0x141/0x2d0 net/ipv6/ip6_input.c:77 ip_sabotage_in+0x1de/0x270 net/bridge/br_netfilter_hooks.c:993 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc2/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:312 __netif_receive_skb_one_core net/core/dev.c:5887 [inline] __netif_receive_skb+0xd3/0x380 net/core/dev.c:6000 netif_receive_skb_internal net/core/dev.c:6086 [inline] netif_receive_skb+0x1cb/0x790 net/core/dev.c:6145 NF_HOOK+0x9d/0x390 include/linux/netfilter.h:315 br_handle_frame_finish+0x1489/0x1950 net/bridge/br_input.c:-1 br_nf_hook_thresh+0x3bf/0x490 net/bridge/br_netfilter_hooks.c:-1 br_nf_pre_routing_finish_ipv6+0x948/0xd00 net/bridge/br_netfilter_ipv6.c:-1 NF_HOOK include/linux/netfilter.h:314 [inline] br_nf_pre_routing_ipv6+0x37e/0x6b0 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:282 [inline] br_handle_frame+0x97f/0x14c0 net/bridge/br_input.c:433 __netif_receive_skb_core+0x10de/0x4180 net/core/dev.c:5773 __netif_receive_skb_one_core net/core/dev.c:5885 [inline] __netif_receive_skb+0x72/0x380 net/core/dev.c:6000 process_backlog+0x60e/0x14f0 net/core/dev.c:6352 __napi_poll+0xc4/0x480 net/core/dev.c:7324 napi_poll net/core/dev.c:7388 [inline] net_rx_action+0x6ea/0xdf0 net/core/dev.c:7510 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 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+0xa6/0xc0 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+0x13/0x20 arch/x86/kernel/paravirt.c:81 Code: cc cc cc cc cc cc cc 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 43 cb 12 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6 RAX: e43bd15558e4d400 RBX: ffffffff81973d78 RCX: e43bd15558e4d400 RDX: 0000000000000001 RSI: ffffffff8d748227 RDI: ffffffff8bc1c820 RBP: ffffc90000197f20 R08: ffff8880b8932b5b R09: 1ffff1101712656b R10: dffffc0000000000 R11: ffffed101712656c R12: ffffffff8f7ebf70 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110038d9b40 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:748 default_idle_call+0x74/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147 net_ratelimit: 9855 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:32:d8:45:c5:7d:d4, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, 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 veth0_to_bridge with own address as source address (addr:32:d8:45:c5:7d:d4, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) net_ratelimit: 11489 callbacks suppressed 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 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:32:d8:45:c5:7d:d4, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)