sched: DL replenish lagged too much rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4901/2:b..l P15578/2:b..l rcu: (detected by 0, t=10503 jiffies, g=114269, q=790816 ncpus=2) task:syz.1.2308 state:R running task stack:23072 pid:15578 tgid:15575 ppid:14941 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6861 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6885 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0x179/0x200 kernel/softirq.c:389 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline] __dev_queue_xmit+0x171d/0x3ed0 net/core/dev.c:4455 dev_queue_xmit include/linux/netdevice.h:3094 [inline] neigh_hh_output include/net/neighbour.h:526 [inline] neigh_output include/net/neighbour.h:540 [inline] ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:236 ip_local_out net/ipv4/ip_output.c:130 [inline] __ip_queue_xmit+0x118c/0x1b80 net/ipv4/ip_output.c:536 __tcp_transmit_skb+0x2544/0x3b30 net/ipv4/tcp_output.c:1466 tcp_transmit_skb net/ipv4/tcp_output.c:1484 [inline] tcp_connect+0x1b7b/0x4940 net/ipv4/tcp_output.c:4143 tcp_v4_connect+0x1127/0x1ba0 net/ipv4/tcp_ipv4.c:341 mptcp_connect+0x701/0xb20 net/mptcp/protocol.c:3792 __inet_stream_connect+0x262/0xf30 net/ipv4/af_inet.c:679 inet_stream_connect+0x65/0xa0 net/ipv4/af_inet.c:750 __sys_connect_file net/socket.c:2071 [inline] __sys_connect+0x2d1/0x300 net/socket.c:2088 __do_sys_connect net/socket.c:2098 [inline] __se_sys_connect net/socket.c:2095 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2095 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: 0033:0x7f276437dff9 RSP: 002b:00007f2765157038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f2764536058 RCX: 00007f276437dff9 RDX: 0000000000000010 RSI: 0000000020000000 RDI: 000000000000000a RBP: 00007f27643f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f2764536058 R15: 00007f276465fa28 task:dhcpcd state:R running task stack:20352 pid:4901 tgid:4901 ppid:4900 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7004 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x0/0x90 kernel/kcov.c:320 Code: 10 48 89 74 0a 18 4c 89 44 0a 20 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 4c 8b 04 24 65 48 8b 0c 25 c0 d7 03 00 65 8b 05 80 eb RSP: 0018:ffffc90002f4f048 EFLAGS: 00000247 RAX: ffffffff8bc0a7c0 RBX: 0000000000000006 RCX: 0000000000000006 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000003f RBP: 0000000000000000 R08: ffffffff8bc0a7b2 R09: ffffffff8bc11fbb R10: 0000000000000002 R11: ffff88802bf80000 R12: ffffc90002f4f1e8 R13: ffff8880234682c2 R14: ffffc90002f4f1f8 R15: 1ffff920005e9e3f xas_start+0x392/0x7b0 lib/xarray.c:195 xas_load+0x2c/0x5c0 lib/xarray.c:238 xas_find+0x13f/0x960 lib/xarray.c:1266 xa_find+0x267/0x420 lib/xarray.c:2057 inet_dump_ifaddr+0x5a2/0x1330 net/ipv4/devinet.c:1901 rtnl_dump_all+0x300/0x520 net/core/rtnetlink.c:4079 rtnl_dumpit+0xa9/0x200 net/core/rtnetlink.c:6535 netlink_dump+0x647/0xd80 net/netlink/af_netlink.c:2326 __netlink_dump_start+0x5a2/0x790 net/netlink/af_netlink.c:2441 netlink_dump_start include/linux/netlink.h:339 [inline] rtnetlink_dump_start net/core/rtnetlink.c:6564 [inline] rtnetlink_rcv_msg+0xb3d/0xcf0 net/core/rtnetlink.c:6631 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2551 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1357 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:744 __sys_sendto+0x39b/0x4f0 net/socket.c:2214 __do_sys_sendto net/socket.c:2226 [inline] __se_sys_sendto net/socket.c:2222 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2222 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: 0033:0x7f4a691c2ad7 RSP: 002b:00007ffcbc79dab8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007ffcbc79ebe0 RCX: 00007f4a691c2ad7 RDX: 0000000000000014 RSI: 00007ffcbc79eb00 RDI: 0000000000000017 RBP: 00007ffcbc79eb70 R08: 00007ffcbc79eae4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000016 R13: 00007ffcbc79eae4 R14: 00007ffcbc79eb00 R15: 0000000000000105 rcu: rcu_preempt kthread starved for 10381 jiffies! g114269 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:25552 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+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 51 Comm: kworker/1:1 Not tainted 6.12.0-rc2-syzkaller-00307-g36c254515dc6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_power_efficient neigh_managed_work RIP: 0010:preempt_count_add+0x44/0x190 kernel/sched/core.c:5793 Code: 00 00 00 fc ff df 42 0f b6 04 38 84 c0 0f 85 ed 00 00 00 83 3d fc ac d9 18 00 75 07 65 8b 05 7b 9b a0 7e 65 01 1d 74 9b a0 7e <48> c7 c0 40 e9 3c 9a 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 e4 00 RSP: 0018:ffffc90000a17c50 EFLAGS: 00000282 RAX: 0000000080000101 RBX: 0000000000000001 RCX: ffffffff9a3ce903 RDX: dffffc0000000000 RSI: ffffffff89e8c35d RDI: 0000000000000001 RBP: ffffc90000a17d78 R08: 0000000000000006 R09: ffffc90000a17e30 R10: ffffc90000a17d90 R11: ffffffff8180a0e0 R12: dffffc0000000000 R13: ffffc90000a17d40 R14: ffffffff89e8c35d R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3253070521 CR3: 0000000064a10000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xb0/0x22d0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kmem_cache_free+0x1a2/0x420 mm/slub.c:4681 nft_synproxy_eval_v4+0x3d2/0x610 net/netfilter/nft_synproxy.c:60 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4ad/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+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5666 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5779 process_backlog+0x662/0x15b0 net/core/dev.c:6111 __napi_poll+0xcb/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+0x2c5/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244