rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=61281, q=698100 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 2432 (4294991478-4294989046), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 2433 jiffies! g61281 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:25200 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 101 PID: 4892 Comm: dhcpcd Not tainted 6.12.0-rc3-syzkaller-00013-geca631b8fe80 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__seqprop_spinlock_sequence include/linux/seqlock.h:227 [inline] RIP: 0010:read_seqbegin include/linux/seqlock.h:757 [inline] RIP: 0010:neigh_hh_output include/net/neighbour.h:496 [inline] RIP: 0010:neigh_output include/net/neighbour.h:540 [inline] RIP: 0010:ip6_finish_output2+0xcb4/0x1730 net/ipv6/ip6_output.c:141 Code: b2 50 30 f7 4d 85 ff 75 16 e8 a8 50 30 f7 eb 15 e8 a1 50 30 f7 e8 dc 20 61 01 4d 85 ff 74 ea e8 92 50 30 f7 fb 43 0f b6 04 26 <84> c0 0f 85 fe 01 00 00 45 8b 7d 00 44 89 fe 83 e6 01 31 ff e8 b3 RSP: 0018:ffffc90000a17d60 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88802c8c1e00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000a17eb8 R08: ffffffff8a64968f R09: 1ffffffff2859106 R10: dffffc0000000000 R11: fffffbfff2859107 R12: dffffc0000000000 R13: ffff8881e0fff1d0 R14: 1ffff1103c1ffe3a R15: 0000000000000200 FS: 00007f07d5e83740(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020c50030 CR3: 000000001eaae000 CR4: 0000000000350ef0 Call Trace: ip6_finish_output+0x41e/0x810 net/ipv6/ip6_output.c:226 synproxy_send_tcp_ipv6+0x568/0x7c0 net/netfilter/nf_synproxy_core.c:851 synproxy_send_client_synack_ipv6+0x7d0/0xc30 net/netfilter/nf_synproxy_core.c:897 nft_synproxy_eval_v6 net/netfilter/nft_synproxy.c:90 [inline] nft_synproxy_do_eval+0x739/0xa60 net/netfilter/nft_synproxy.c:145 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4af/0x1da0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a6/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5666 [inline] __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5779 process_backlog+0x662/0x15b0 net/core/dev.c:6111 __napi_poll+0xcd/0x490 net/core/dev.c:6775 napi_poll net/core/dev.c:6844 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6966 handle_softirqs+0x2c7/0x980 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:qlist_free_all+0x9d/0x140 mm/kasan/quarantine.c:174 Code: 83 c0 00 00 00 49 29 c4 48 89 df 4c 89 e6 e8 4a e5 ff ff 66 90 48 8d 15 00 00 00 00 48 89 df 4c 89 e6 e8 56 05 f4 ff 4d 85 f6 <75> 8b eb 65 f3 0f 1e fa 48 83 7b 48 00 75 dc 0f b7 4b 08 f7 c1 04 RSP: 0018:ffffc90004a6fa00 EFLAGS: 00000286 RAX: 7179adf404955700 RBX: ffff88801bebadc0 RCX: 0000000000110001 RDX: 0000000000110002 RSI: ffffea0000bc2fc0 RDI: ffff88801bebadc0 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff81fea8af R10: dffffc0000000000 R11: fffffbfff2859107 R12: ffff88802f0bf2d0 R13: ffffea0000000000 R14: ffff88802f0bf3c0 R15: 0000000000000000 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] __do_kmalloc_node mm/slub.c:4263 [inline] __kmalloc_noprof+0x1a6/0x400 mm/slub.c:4276 kmalloc_noprof include/linux/slab.h:882 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x26f/0x540 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x59e/0x5e0 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_number_perm+0x23a/0x880 security/tomoyo/file.c:723 security_file_ioctl+0xc6/0x2a0 security/security.c:2910 __do_sys_ioctl fs/ioctl.c:901 [inline] __se_sys_ioctl+0x47/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f07d5f51d49 Code: 5c c3 48 8d 44 24 08 48 89 54 24 e0 48 89 44 24 c0 48 8d 44 24 d0 48 89 44 24 c8 b8 10 00 00 00 c7 44 24 b8 10 00 00 00 0f 05 <41> 89 c0 3d 00 f0 ff ff 76 10 48 8b 15 ae 60 0d 00 f7 d8 41 83 c8 RSP: 002b:00007ffd48202f18 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00005573679a0c40 RCX: 00007f07d5f51d49 RDX: 00007ffd48202f20 RSI: 0000000000008921 RDI: 0000000000000011 RBP: 0000000000000000 R08: 0000000000000008 R09: 0000000000000036 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd48202f20 R13: 00005573453b5f88 R14: 00005573679a0c40 R15: 00005573679a47a0