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): P12696/1:b..l rcu: (detected by 0, t=10503 jiffies, g=80829, q=1037 ncpus=2) task:syz.8.1210 state:R running task stack:25032 pid:12696 tgid:12694 ppid:12319 task_flags:0x40044c flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6970 preempt_schedule+0xae/0xc0 kernel/sched/core.c:6994 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:414 spin_unlock_bh include/linux/spinlock.h:396 [inline] cfg80211_mlme_unregister_socket+0x2ce/0x690 net/wireless/mlme.c:761 nl80211_netlink_notify+0x356/0x840 net/wireless/nl80211.c:20301 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380 netlink_release+0x1259/0x1b10 net/netlink/af_netlink.c:764 __sock_release net/socket.c:647 [inline] sock_close+0xc3/0x240 net/socket.c:1391 __fput+0x44c/0xa70 fs/file_table.c:465 task_work_run+0x1d1/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x22e0 kernel/exit.c:964 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105 get_signal+0x1286/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2dff18e929 RSP: 002b:00007f2e000c40e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f2dff3b5fa8 RCX: 00007f2dff18e929 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2dff3b5fa8 RBP: 00007f2dff3b5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2dff3b5fac R13: 0000000000000000 R14: 00007f2dff4df940 R15: 00007f2dff4dfa28 rcu: rcu_preempt kthread starved for 7424 jiffies! g80829 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:27128 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5401 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6790 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7113 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__free_object+0x4fb/0x6c0 lib/debugobjects.c:524 Code: a5 ff fc 48 c7 44 24 60 00 00 00 00 9c 8f 44 24 60 f6 44 24 61 02 75 53 f7 c3 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <48> 8b 44 24 38 4a c7 04 28 00 00 00 00 66 42 c7 44 28 09 00 00 42 RSP: 0018:ffffc900001578e0 EFLAGS: 00000206 RAX: 3a86a3a5dc9ac800 RBX: 0000000000000a06 RCX: 3a86a3a5dc9ac800 RDX: 0000000000000000 RSI: ffffffff8d997600 RDI: ffffffff8be29580 RBP: ffffc900001579d0 R08: ffffffff8fa1e5f7 R09: 1ffffffff1f43cbe R10: dffffc0000000000 R11: fffffbfff1f43cbf R12: ffff8880b873b9c8 R13: dffffc0000000000 R14: ffff8880b873b9c0 R15: 1ffff110170e7739 free_object lib/debugobjects.c:532 [inline] debug_object_free+0x2a2/0x340 lib/debugobjects.c:976 schedule_timeout+0x13b/0x270 kernel/time/sleep_timeout.c:103 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 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 6.16.0-rc5-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:100 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline] RIP: 0010:unwind_next_frame+0x12ea/0x2390 arch/x86/kernel/unwind_orc.c:494 Code: 40 3a 88 8b 89 de e8 35 f1 b4 ff e9 43 06 00 00 49 89 d5 48 89 d5 48 89 d8 48 29 e8 48 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 <48> 83 e0 fe 4c 8d 3c 45 00 00 00 00 49 01 ef 4c 89 f8 48 c1 e8 03 RSP: 0018:ffffc90000a07b78 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff8fbe89e8 RCX: 0000000000000000 RDX: ffffffff8fbe89bc RSI: ffffffff903ec906 RDI: ffffffff8be29520 RBP: ffffffff8fbe89e8 R08: 0000000000000015 R09: ffffffff81729af5 R10: ffffc90000a07c98 R11: ffffffff81acf330 R12: ffffffff822376cb R13: ffffffff8fbe89e4 R14: ffffc90000a07c48 R15: ffffffff8fbe89ec FS: 0000000000000000(0000) GS:ffff888125d1d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faf0a400000 CR3: 0000000067044000 CR4: 00000000003526f0 DR0: 0000000000000007 DR1: 0000000000000002 DR2: 0000000000000008 DR3: 1000000100000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4249 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:660 alloc_skb include/linux/skbuff.h:1336 [inline] synproxy_send_client_synack_ipv6+0x169/0xca0 net/netfilter/nf_synproxy_core.c:873 nft_synproxy_eval_v6+0x36e/0x560 net/netfilter/nft_synproxy.c:90 nft_synproxy_do_eval+0x3d7/0x570 net/netfilter/nft_synproxy.c:145 expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline] nft_do_chain+0x40c/0x1920 net/netfilter/nf_tables_core.c:285 nft_do_chain_inet+0x25d/0x340 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_slow+0xc2/0x220 net/netfilter/core.c:623 nf_hook include/linux/netfilter.h:272 [inline] NF_HOOK+0x206/0x3a0 include/linux/netfilter.h:315 ip6_input+0x16a/0x270 net/ipv6/ip6_input.c:491 NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:317 __netif_receive_skb_one_core net/core/dev.c:5977 [inline] __netif_receive_skb+0xd3/0x380 net/core/dev.c:6090 process_backlog+0x60e/0x14f0 net/core/dev.c:6442 __napi_poll+0xc7/0x480 net/core/dev.c:7414 napi_poll net/core/dev.c:7478 [inline] net_rx_action+0x707/0xe30 net/core/dev.c:7605 handle_softirqs+0x286/0x870 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:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 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:82 Code: 03 de 02 00 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 03 26 19 00 f3 0f 1e fa fb f4 d8 dd 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2 RAX: 434f8605afc69500 RBX: ffffffff81975c78 RCX: 434f8605afc69500 RDX: 0000000000000001 RSI: ffffffff8d997600 RDI: ffffffff8be29580 RBP: ffffc90000197f20 R08: ffff8880b8732f5b R09: 1ffff110170e65eb R10: dffffc0000000000 R11: ffffed10170e65ec R12: ffffffff8fa1e5f0 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003a5eb40 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:749 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