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): P5217/1:b..l rcu: (detected by 1, t=10503 jiffies, g=10821, q=1676759 ncpus=2) task:udevd state:R running task stack:23120 pid:5217 tgid:5217 ppid:4683 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6997 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:__kernel_text_address+0xd/0x40 kernel/extable.c:79 Code: e8 e8 ce 9e 00 eb b5 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 53 48 89 fb e8 43 00 00 00 <85> c0 0f 95 c0 48 c7 c1 00 90 7b 91 48 39 cb 0f 93 c1 48 c7 c2 ff RSP: 0018:ffffc9000384f630 EFLAGS: 00000287 RAX: 0000000000000001 RBX: ffffffff81fe32a3 RCX: 0000000080000000 RDX: dffffc0000000000 RSI: ffffc90003848000 RDI: ffffffff81fe32a3 RBP: ffffc9000384f6f0 R08: ffffc9000384fb20 R09: 0000000000000000 R10: ffffc9000384f6b0 R11: fffff52000709ed8 R12: ffff888011f3da00 R13: ffffffff81806870 R14: dffffc0000000000 R15: 1ffff92000709ed5 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xfd/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x76/0x430 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638 __slab_free+0x31b/0x3d0 mm/slub.c:4491 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 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:4086 [inline] slab_alloc_node mm/slub.c:4135 [inline] __do_kmalloc_node mm/slub.c:4264 [inline] __kmalloc_node_noprof+0x1d2/0x440 mm/slub.c:4271 __kvmalloc_node_noprof+0x72/0x190 mm/util.c:658 seq_buf_alloc fs/seq_file.c:38 [inline] seq_read_iter+0x20c/0xd70 fs/seq_file.c:210 new_sync_read fs/read_write.c:488 [inline] vfs_read+0x9bb/0xbc0 fs/read_write.c:569 ksys_read+0x183/0x2b0 fs/read_write.c:712 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: 0033:0x7f5d65916b6a RSP: 002b:00007ffdb1a93068 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000559412fdc320 RCX: 00007f5d65916b6a RDX: 0000000000001000 RSI: 0000559413031e70 RDI: 0000000000000009 RBP: 0000559412fdc320 R08: 0000000000000009 R09: 0000000000000008 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffdb1a93548 R15: 000000000000000a rcu: rcu_preempt kthread starved for 10477 jiffies! g10821 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:25888 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5278 Comm: kworker/0:4 Not tainted 6.11.0-syzkaller-11504-g44badc908f2c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:ipv4_synproxy_hook+0x928/0x1040 net/netfilter/nf_synproxy_core.c:749 Code: 00 bb 01 00 00 00 49 bc 00 00 00 00 00 fc ff df 48 c7 44 24 60 0e 36 e0 45 4b c7 04 2c 00 00 00 00 43 c7 44 2c 0a 00 00 00 00 <66> 43 c7 44 2c 0e 00 00 65 48 8b 04 25 28 00 00 00 48 3b 84 24 e0 RSP: 0018:ffffc90000006d60 EFLAGS: 00000246 RAX: ffffffff89e77722 RBX: 0000000000000001 RCX: ffff88802e94bc00 RDX: 0000000000000100 RSI: ffff88806203c600 RDI: 0000000000000000 RBP: ffffc90000006e88 R08: ffffffff89e77598 R09: 0000000000000000 R10: ffffc90000006e00 R11: fffff52000000dc2 R12: dffffc0000000000 R13: 1ffff92000000db8 R14: ffff88820572bb40 R15: ffff88806203c603 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31f1eff8 CR3: 0000000024702000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook+0x2c4/0x450 include/linux/netfilter.h:269 NF_HOOK_COND include/linux/netfilter.h:302 [inline] ip_output+0x185/0x230 net/ipv4/ip_output.c:434 synproxy_send_client_synack+0x8b8/0xf30 net/netfilter/nf_synproxy_core.c:484 nft_synproxy_eval_v4+0x3ca/0x610 net/netfilter/nft_synproxy.c:59 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:5662 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5775 process_backlog+0x662/0x15b0 net/core/dev.c:6107 __napi_poll+0xcb/0x490 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6962 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 neigh_periodic_work+0xb35/0xd50 net/core/neighbour.c:1019 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