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): P3504/1:b..l P17603/1:b..l rcu: (detected by 0, t=10503 jiffies, g=72685, q=1502999 ncpus=2) task:syz.1.3486 state:R running task stack:26160 pid:17603 tgid:17591 ppid:14563 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 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:stack_trace_consume_entry+0x15/0x280 kernel/stacktrace.c:83 Code: 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 18 48 89 fb <48> ba 00 00 00 00 00 fc ff df 4c 8d 4f 10 4d 89 cf 49 c1 ef 03 41 RSP: 0000:ffffc9000cc677b0 EFLAGS: 00000282 RAX: ffffffff8223e10f RBX: ffffc9000cc678e0 RCX: ffffffff91772000 RDX: ffffffff91920f01 RSI: ffffffff8223e10f RDI: ffffc9000cc678e0 RBP: ffffc9000cc67890 R08: ffffc9000cc6785f R09: 0000000000000000 R10: ffffc9000cc67850 R11: ffffffff818b35d0 R12: ffff88803563bc00 R13: ffffffff818b35d0 R14: ffffc9000cc678e0 R15: 0000000000000000 arch_stack_walk+0x10e/0x150 arch/x86/kernel/stacktrace.c:27 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:1127 [inline] free_unref_page+0xde3/0x1130 mm/page_alloc.c:2657 discard_slab mm/slub.c:2673 [inline] __put_partials+0xeb/0x130 mm/slub.c:3142 put_cpu_partial+0x17c/0x250 mm/slub.c:3217 __slab_free+0x2ea/0x3d0 mm/slub.c:4468 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_kmalloc+0x23/0xb0 mm/kasan/common.c:385 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4283 [inline] __kmalloc_node_track_caller_noprof+0x28b/0x4c0 mm/slub.c:4302 memdup_user+0x2b/0xc0 mm/util.c:218 strndup_user+0x68/0xc0 mm/util.c:277 copy_mount_string fs/namespace.c:3742 [inline] __do_sys_mount fs/namespace.c:4042 [inline] __se_sys_mount+0x9f/0x3c0 fs/namespace.c:4034 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: 0033:0x7ff48a980849 RSP: 002b:00007ff4887b4058 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007ff48ab46160 RCX: 00007ff48a980849 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 00007ff48a9f3986 R08: 00000000200001c0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff48ab46160 R15: 00007ffe58dc8ef8 task:kworker/u8:9 state:R running task stack:20560 pid:3504 tgid:3504 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 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:lock_acquire+0x28d/0x550 kernel/locking/lockdep.c:5853 Code: 45 4b c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 11 00 00 00 00 66 43 c7 44 25 15 00 00 43 c6 44 25 17 00 <65> 48 8b 04 25 28 00 00 00 48 3b 84 24 00 01 00 00 0f 85 95 02 00 RSP: 0018:ffffc9000c9ef9e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200193df48 RCX: ffff8880326d46d8 RDX: dffffc0000000000 RSI: ffffffff8c0aa880 RDI: ffffffff8c5e90a0 RBP: ffffc9000c9efb40 R08: ffffffff94282887 R09: 1ffffffff2850510 R10: dffffc0000000000 R11: fffffbfff2850511 R12: 1ffff9200193df44 R13: dffffc0000000000 R14: ffffc9000c9efa40 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 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 rcu: rcu_preempt kthread starved for 9170 jiffies! g72685 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:25976 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 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: CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.12.0-syzkaller-12113-gbcc8eda6d349 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:arch_stack_walk+0x123/0x150 arch/x86/kernel/stacktrace.c:24 Code: 03 aa 09 00 48 85 c0 74 23 4c 89 f7 48 89 c6 4d 89 eb 41 ff d3 66 90 84 c0 74 11 48 89 df e8 34 ab 09 00 83 bd 70 ff ff ff 00 <75> d0 65 48 8b 04 25 28 00 00 00 48 3b 45 d0 75 13 48 83 c4 68 5b RSP: 0018:ffffc90000156520 EFLAGS: 00000202 RAX: 0000000080000101 RBX: ffffc90000156520 RCX: 0000000080000100 RDX: dffffc0000000000 RSI: ffffc90000150000 RDI: 0000000000000001 RBP: ffffc900001565b0 R08: ffffc90000157f20 R09: 0000000000000000 R10: ffffc90000156570 R11: fffff5200002acb0 R12: ffff88801cecda00 R13: ffffffff818b35d0 R14: ffffc90000156600 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32b0fff8 CR3: 000000000e736000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 000000000000000a DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4104 [inline] slab_alloc_node mm/slub.c:4153 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4160 dst_alloc+0x12b/0x190 net/core/dst.c:89 rt_dst_alloc net/ipv4/route.c:1625 [inline] __mkroute_output net/ipv4/route.c:2617 [inline] ip_route_output_key_hash_rcu+0x13cc/0x2390 net/ipv4/route.c:2839 ip_route_output_key_hash+0x193/0x2b0 net/ipv4/route.c:2668 __ip_route_output_key include/net/route.h:141 [inline] ip_route_output_flow+0x29/0x140 net/ipv4/route.c:2896 ip_route_output_key include/net/route.h:151 [inline] ip_route_me_harder+0x877/0x1360 net/ipv4/netfilter.c:53 synproxy_send_tcp+0x356/0x6c0 net/netfilter/nf_synproxy_core.c:431 synproxy_send_client_synack+0x8a4/0xe20 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:5672 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5785 process_backlog+0x662/0x15b0 net/core/dev.c:6117 __napi_poll+0xcb/0x490 net/core/dev.c:6877 napi_poll net/core/dev.c:6946 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7068 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:943 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 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